NC0024406_BC CSA Update 2017 Appendix A_20171031

2017 Comprehensive Site Assessment Update
Belews Creek Steam Station
FIT93TTOT M111
REGULATORY CORRESPONDENCE
October 2017
SynTerra
NCDEQ Expectations Document (July 18, 2017)
Completed DEQ CSA Update Expectations Check List
NCDENR NORR Letter (August 13, 2014)
Revised Interim Monitoring Network
(October 19, 2017)
NCDEQ Background Dataset Review (July 7, 2017)
Zimmerman To Draovitch (September 1, 2017)
NCDEQ Background Threshold Value Approval
Attachments (September 1, 2017)

2017 Comprehensive Site Assessment Update October 2017
Belews Creek Steam Station
DEQ EXPECTATIONS DOCUMENT
(JULY 18, 2017)
SynTerra

DRAFT
Review of Draft Final Updated CSA Table of Contents submitted by Duke Energy July 18, 2017
The Updated Comprehensive Site Assessment Report(CSAs) must meet the requirements of 02L.0106
(g), CAMA, and general guidelines provided in the Notice of Regulatory Requirements letter from DEQ to
Duke on August 13, 2014.
Pursuant to 02L .0106 (g), the CSAs shall:
• Identify the source and cause of contamination,
• Identify imminent hazards and document actions taken to mitigate them,
• Identify all receptors,
• Define the horizontal and vertical extent of contamination,
• Understand all significant factors affecting contaminant transport,
• Understand geological and hydrogeological factors influencing the movement, chemical, and
physical character of the contaminants.
It is the expectation that the CSA report be a stand-alone document that integrates, interprets, and
presents all data/information collected to date. The table of contents submitted on 7/18/17 should be
revised as necessary to ensure that the following comments are reflected in the CSA report.
1. Site history
• Facility description, geographic setting, surrounding land use, permitting history, and
compliance boundaries and permitted sampling, etc.
• ash related history
• history prior to Duke ownership
• history of waste releases unrelated to coal ash
2. Identification of source areas'
3. Identification of potential receptors
• Surface water
o Is the SW used as drinking water supply? if so, what is the distance to intake?
• Supply wells
o Need map and table showing all receptors identified
o Has each identified supply well been abandoned and connected to alternative
permanent water?
' Large ash basins or other waste areas may need to be divided into separate smaller source areas if, for example,
contaminant transport is toward different sets of receptors. Where appropriate, some source areas may be strategically
combined based on geographic proximity (for example, conjoining or overlapping source areas), common source
characteristics and impacts, common receptors, and a shared proposed remedy. The Regional Office should be
consulted when identifying source areas for purposes of CSA and CAP development.
Page 1 of 8

• Evaluation: Are COls in supply wells above 2L/IMAC/background and sourced by ash?
4. Raw data collected to date
• A separate orthophoto base ma P2 should be provided for each of the following:
o All GW monitoring and supply wells
■ Show screened interval (ft) and most recent concentration of boron and COls
(ug/L) (use different color font for each flow unit)
o All SW, seep, and effluent channel (permitted) sample locations
■ Show most recent results of boron and COls (ug/L)
o All SW locations sampled specifically to determine whether contaminated GW is
causing 2B violations
■ Show most recent results of boron and COls (ug/L); use bold font for values
that exceeded 2B standards (ug/L)
o All solid phase sample locations, to include ash, soil, and sediment locations
■ Show sample depth (ft bls) and corresponding concentration of COls (mg/kg)
o Location, flow unit, screened/open interval (ft bls), and value (ft/d) of hydraulic
conductivity (k) measurements (use different color font for each flow unit)
o Location, depth (ft bls), and flow unit of soil -water pairs (use different color font for
each flow unit)
o Location, depth (ft bls), flow unit, and value of HFO measurements (use different color
font for each flow unit)
o Location, depth (ft bls), and flow unit of sorption coefficient (Kds) measurements (use
different color font for each flow unit)
o Location, flow unit, and value of pH measurements (use different color font for each
flow unit)
o Location, flow unit, and value of Eh measurements (mV) (use different color font for
each flow unit)
o Location of vertical gradient calculations between shallow/TZ unit and BR unit, showing
value (+ is downward gradient, - is upward gradient)
Cross section maps showing ash position, hydrostratigraphy, screen/open intervals, water
level, and groundwater boron and COI concentrations (ug/L)
o inset should show location (in plan view) of the cross section
Summary data tables:
o properties for ash, fill, alluvium, soil/saprolite, deep, and bedrock units, as applicable,
including:
■ Porosity
■ Specific storage
■ Permeability (field, lab, historic)
■ Mineralogy and oxides
■ Physical
Methodology, computations, etc. may be referenced, as applicable
o hydraulic conductivities (k, in ft/d), sorted by flow unit, along with well identifier, flow
unit, and screened/open interval (ft bls)
o sorption coefficients (Kd), sorted by COI then flow unit, along with boring location
identifier, flow unit, and depth (ft bls)
2 All base maps should include2 to 4 foot topographic contours, all surface water features, all jurisdictional
wetlands, all source areas along with waste boundaries and compliance boundaries if applicable, all monitor wells,
and, where scale allows, all supply wells.
Page 2 of 8

• Appendices
o Raw data tables showing chemistry results for:
■ all GW, SW, and seep sample events (appendix and digital excel file)
■ all ash, soil, sediment, and whole rock chemistry results (appendix and digital
excel file)
■ all SPLP samples (appendix and digital excel file)
■ lat/long, flow unit (if applicable), etc. should be included for each sample
location
■ current "master spreadsheet" format may be used
■ lab QC data may be referenced if it has already been provided in a separate
report
o Summary table of monitor well construction details showing well, location (decimal
degree lat/long), screen/open interval, depth to water, date installed, flow unit being
monitored, date abandoned if applicable, etc.
o Water level measurements from all wells and current and historical measurement
events (appendix and digital excel file)
■ List of wells that were dry during sampling or measurement attempts, along
with its flow unit, screened/open interval, and date
o Sorption coefficient testing - methodology, raw data, and computations may be
referenced
o Boring logs and well construction records
■ Include all assessment, historic, CCR, or other wells installed to date
■ Each log should be quality controlled for accuracy and include static WL
information.
o Geophysical logs, rose diagrams, lineament map
o Soil and rock photos
o Most recent pre -ash basin USGS topographic map, with superimposed source areas
o Screening level risk assessment
■ Human health
■ Ecological
o Flow and transport model
o Geochemical model
o GW -SW mixing model, if applicable
5. Site conceptual model
• Overview of the major components, including source(s), hydrologic boundaries, migration
pathway(s), receptors, etc.
• Regional geology and how it is affecting GW flow, GW quality, and contaminant transport at the
site
• Hydrostratigraphy (flow units)
o Flow properties and heterogeneities of each unit
■ Discuss hydraulic conductivities and vertical gradients (refer to maps in 4.
above)
■ Describe where flow units pinch out in each unit, as applicable
■ Discuss fractured bedrock heterogeneities across the site, including ranges of
hydraulic conductivities and porosities
■ Discuss maximum depth of investigation and observed fracture density with
depth; compare this to the depths of proximate supply wells
Page 3 of 8

• Areas of recharge and discharge
• Flow directions
o Potentiometric map (summer) of shallow/TZ unit
o Potentiometric map (winter) of shallow/TZ unit
o Potentiometric map (summer) of bedrock unit
o Potentiometric map (winter) of bedrock unit
■ Potentiometric maps should utilize and show all facility wells, should clearly
show all blue line tributaries, wetlands, and other SWs, and should indicate
areas where a flow unit pinches out as applicable
o Evaluation: Do seasonal or tidal influences effect GW flow or GW chemistry?
6. Background concentrations (PBTVs) of soil and groundwater.
• Piper diagrams for shallow b/g, deep b/g, and bedrock b/g, along with well labels for plotted
points
• List PBTVs for soil
• List PBTVs for groundwater, by flow unit
• Methodology (appendix)
• Description of background wells (why those chosen are appropriate for use) and soil sample
locations (appendix)
• Table of all raw background data showing strikethroughs of unused high pH, high turbidity,
autocorrelated, and outlier data (appendix; digital excel file)
7. Contaminant assessment
For each source area,
• History of ash placement
• Area, depth, and volume of ash (include also the area, depth, and volume of
saturated/submerged ash)
• Status of source removal or control
• Orthophoto base map (large scale, 1 inch — 100 feet) showing waste boundary, compliance
boundary if applicable, 2 to 4 ft topographic contours, all blue line surface water and wetland
features, along with the following:
o subset of supply well and SW receptors from 3. above that are potentially susceptible to
contaminant migration from this particular source area
■ Include inset table with list of supply wells and SW receptors for this source area
o monitor wells, supply wells, and SW, seep, ash, soil, and sediment locations
■ Indicate most recent value (ug/L) for boron and for each COI, and whether its
concentration is increasing, decreasing, stable, or unknown
• Evaluation: Show a vertical gradient isopleth map and discuss vertical gradients and their effect
on GW flow
• List COls (constituents above 02L/IMAC/background) for each flow unit beyond compliance
boundary (or that are within bedrock monitor wells within or beyond compliance boundary if
receptors are potentially at risk)
• List pH and Eh ranges found in: pore water, d/g shallow unit, d/g TZ unit, and d/g BR unit
• Evaluation: Explain the geochemical controls on COls that do not behave as a plume (Fe, Mn,
etc.).
Page 4 of 8

Evaluation: Use the pH, Eh, Kd, and HFO results to discuss the expected capacity of the
subsurface to sorb cationic COls and anionic COls occurring from source to receptor within each
of the flow units.
• Provide the following "data inventory":
o (a) have background concentrations been formally established for all COls in soil and
groundwater?
o (b) for each source area, how many wells within each flow system are located along the
contaminant plume centerline? Along a cross sectional transect that is perpendicular to
the plume centerline?
o (c) how many wells in (b) above are screened across the most contaminated vertical
interval of a given flow unit or are screened across the full thickness of the flow unit?
o (d) is the d/g edge of the plume centerline measured or is this location obstructed by a
major SW or other access issue? If so, is it measured by wells that are screened across
each flow unit?
o (d) what is the length of record and how many valid sample events are available for
wells listed in (b), (c), and (d) above?
o (e) does turbidity, well construction (for example, grout contamination, etc.), or well
"break in" issues preclude the use of data in (b), (c), and (or) (d)?
o (f) for each source area and within each flow unit, how many spatial locations were
sampled for solid phase chemistry and were these locations associated with "end
member" (maximum and minimum) groundwater concentrations for each
contaminantl"? How many of these spatial locations are associated with (b) or (c)
above?
o (g) given that iron hydroxide (HFO) content is a good indicator of retention capacity for
most metal contaminants, how many locations in (f) was HFO measured?
For each COI in this particular source area,
o Evaluation: Were wells properly positioned and screened to measure the horizontal and
vertical extent of the plume? If so, describe the horizontal and vertical plume extent
using plan view and cross sectional maps.
o Has the plume migrated to any supply wells, SW receptors, or GW future use areas?
o Has the plume migrated to any supply wells, SW receptors, or GW future use areas at
concentrations above 2L/IMAC/background?
o Evaluation: Were wells positioned and screened to measure the maximum
concentrations migrating from source to receptor along the longitudinal plume
centerline? If so, describe the plume characteristics is space and time as it flows along
the centerline, through the identified flow units, and discharges into the nearest supply
well or SW receptor.
o Evaluation: Use maps, graphs, statistics, and mass movement or balance equations to
show whether the plume is expanding and whether the plume is moving.
■ Show the COI -distance plot of wells positioned along a plume centerline from
source to farthest d/g location (closest to receptor or future use area.
Ill Measuring the solid phase contaminant concentrations in locations of both low and high groundwater C01
concentrations are important in understanding the sorptive capacity of the system. This is particularly true in the
case of non-linear isotherm adsorption models that describe most metals. That is, a soil has a limited ability to
sorb contaminant mass due, for example, to limited sorption sites, so a soil can become less efficient at removing
mass at higher dissolved concentrations.
Page 5 of 8

■ If applicable, show COI -distance plots at different timepoints to demonstrate
potential plume expansion or migration.
■ If applicable and sufficient sample events are available, use single -well linear
regression or Mann-Kendall/Theil-Sen type trend statistics to show increasing or
decreasing trends at selected d/g monitor wells.
o Describe the soil -water pairs and Kd lab test sample results. Describe where they were
collected, why those locations were selected, and whether those locations are reflective
of high and low COI concentrations in a given flow unit.
o Show concentration isopleths for each COI, including contours of concentrations below
and well above the 2L/IMAC (choose — five contours per COI, from "moderately low" to
"high")
o Show stacked boron -time plots of wells positioned along a plume centerline from source
to farthest d/g location (closest to receptor)
Summary of corrective actions taken to date, if applicable
• Describe preliminary corrective action alternatives for this source area
f:� .. u . •.Cal
• Description of model
• Model construction — domain, layers, boundary conditions, recharge and discharge areas, supply
wells, hydraulic conductivities, stream conductances, etc.
o Layer thicknesses in cross section (show vertical scale in feet)
o Location of supply wells outside model domain
• Calibration method
o List of target wells used in calibration
o List of monitor wells not used in calibration and the rationale for each that was omitted
• Calibration results (where mapped, superimpose on orthophoto base map described above)
o Hydraulic conductivity zones versus measured values for the zone
o List of simulated versus observed heads (include wells and SW features)
o List of simulated versus observed vertical gradients from well pair locations
o List of simulated versus observed discharge to streams
o Potentiometric surface
■ Simulated for each flow layer
■ Observed, shallow
■ Observed, deep
■ Observed, BR
o Flow paths (particle tracks) from each source area
o Reverse flow paths (particle tracks) from SW receptors
o Reverse flow paths (particle tracks) from supply wells (because supply wells are usually
open from casing (at —50 to 75 ft) down to 200 to 500 feet, release particles in all
simulated bedrock layers)
• Quantitative sensitivity analyses to key inputs at various selected d/g locations
• Describe the most significant model limitations
9. Transport model
• Description of model
• Model construction — boundary conditions, time steps, initial conditions, etc.
o Source loading, per layer
o Background concentrations, per layer
Page 6 of 8

o Initial Kds, per layer
o Dispersivities, per layer
o Effective porosities, per layer
• Calibration method
o List of target wells used in calibration
o List of monitor wells not used in calibration and the rationale for each that was omitted
o Calibrated Kds, per layer
• Calibration results (where mapped, superimpose on orthophoto base map described above)
o List of simulated versus observed concentrations in target wells
o List of simulated concentrations in SW discharge locations as shown using particle tracks
released from source areas
o List of simulated versus observed concentrations in selected well pair locations
• Boron isopleth map
■ Simulated for each flow layer
■ Observed, shallow
■ Observed, deep
■ Observed, BR
• For each source area, the time, direction, and distance of contaminant travel must be predicted
under existing conditions and under any other contemplated source control measure (for
example, engineered cap and (or) excavation). For these scenarios, the following figures are
expected:
o (a) a concentration -time plot for each COI corresponding to the following locations: (i)
nearest supply well, (ii) nearest future groundwater use area, and (iii) nearest surface
water.
■ In the plot margin, the following information should be provided: the time it
takes for the COI to reach (i), (ii), and (iii), the time it takes for the COI to reach
(i), (ii), and (iii) at its 2L/IMAC concentration, the time it takes for the COI to
reach (i), (ii), and (iii) at its maximum concentration, and the time it takes for the
COI to reach (i), (ii), and (iii) at a concentration that is back below the 2L/IMAC
concentration.
o (b) a map superimposed on the requested base map showing the maximum predicted
migration distance, at any detectable concentration, of each COI.
o (c) a map superimposed on the requested base map showing the maximum predicted
migration distance, at the 2L/IMAC standard concentration, of each COI.
• Quantitative sensitivity analyses to key inputs at various selected d/g locations and times
• Describe the most significant model limitations
10. Geochemical model for COls controlled primarily by geochemistry
• Conceptual model based on observed site data
o Describe geochemical controls on COI levels in each source area using site data
o Assumptions used in developing the model
o Discuss data used to develop the model
■ For example, how are mineral or adsorption concentrations in fractured media
converted to PHREEQC concentrations representing reaction along the fractures?
■ How were modeled reactive mineral concentrations interpolated between or
extrapolated from the limited number of data collected
Page 7 of 8

o Discuss what the COI concentrations are most sensitive to (pH, Eh, iron/aluminum oxide
content, Kd, distance from source, etc.)
o Describe the most significant limitations of the model
• Numerical model (PHREEQC or PHREEQC 1-D Transport model)
o Description of model
o Purpose of model
o Model construction
o Discuss data used to develop the flow model
o Results with comparison to observed well data (PHREEQC model) or to longitudinal flow
path transect data (PHREEQC 1-D Transport model)
o Sensitivity analysis (to pH, Eh, Kd, COI concentration, total dissolved ion content,
iron/aluminum oxide content, Kd, distance from source, etc.)
o Describe the most significant limitations of the model
11. GW -SW mixing model
• Description of model
• Purpose of model
• Model construction
o Show on map the precise SW locations where model output (simulated SW
concentration) was obtained
o List and discuss data used to construct model
■ Permitted effluent discharge concentrations should be considered in the model
construction
o Assumptions
• Results
• Sensitivity analysis (to GW contaminant concentrations, permitted effluent concentrations,
location where SW output was obtained, stream flow, nearby effluent loading to the SW, etc.)
• Describe the most significant limitations of the model
Page 8 of 8

2017 Comprehensive Site Assessment Update October 2017
Belews Creek Steam Station
SynTerra
DEQ CSA UPDATE EXPECTATIONS - CHECK LIST

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
NCDEQ provided extensive expectations to be included in the CSA Update, in
addition to NORR (August 2014) guidance. The following is a guide to locate the
requests in the CSA Update Report:
DEQ Expectations JReport
1. Site History
Facility description, geographic setting, surrounding
land use, permitting history, and compliance
Section 2.0
boundaries and permitted sampling, etc.
ash related history
Section 2.0
history prior to Duke ownership
Section 2.1
history of waste releases unrelated to coal ash Section 2.7
'Large ash basins or other waste areas may need to be
Sections 2.3, 2.4,
divided into separate smaller source areas if, for
and 3.0
example, contaminant transport is toward different sets
of receptors. Where appropriate, some source areas
may be strategically combined based on geographic
proximity (for example, conjoining or overlapping
source areas), common source characteristics and
impacts, common receptors, and a shared proposed
remedy. The Regional Office should be consulted when
identifying source areas for purposes of CSA and CAP
development.
Identification
of
Potential3.
Duke to provide information on where new water lines
Appendix D &
are planned, estimated new water line taps, and
Section 4.0
projected location for filtration systems. Duke and DEQ
will work together to provide most recent analytical
analysis for inclusion in CSA.
Surface water :
Sections 4.0 &
Is the SW used as drinking water supply? if so, what is
4.5
the distance to intake?
Supply wells:
Figure 4-2 &
Need map and table showing all receptors identified
Table 4-3
Has each identified supply well been abandoned and
Section 4.0
connected to alternative permanent water?
Evaluation: Are COIs in supply wells above
Section 14.3
2L/IMAC/background and sourced b ash?
Key: Tables — Shaded Blue Figures — Shaded Green CAP — Shaded Red
Page 1 of 13

2017 Comprehensive Site Assessment Update - Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
_DEQ Expectations Report-
Figures:
• All GW monitoring and supply well locations
Figure 2-10 &
Figure 4-2
• Show screened interval (ft. bgs.) and flow unit (use
Figure 14-97
different color call out box for each flow unit)
• Location, flow unit, and value of pH and Eh
measurements
• Most recent concentration of boron and COIs (ug/L)
• Hydraulic conductivity (k) measurement value (ft/d)
if available for corresponding well screen interval
• All SW, AOW seep and effluent channel (permitted)
Figure 14-98
sample locations
— Show most recent results of boron and COIs
(ug/L)
• All solid phase sample locations, to include ash, soil,
Figure 14-99
and sediment locations
• Show sample depth (ft. bgs.) and flow unit
• Concentration of COIs (mg/kg)
• Location, depth (ft. bgs.) and flow unit of soil -water
pairs shown as blue color font
• Location, depth (ft. bgs.), flow unit for HFO
measurements and value (mg/Kg)
• Location, depth (ft. bgs.), flow unit for sorption
coefficient (Kds) measurements and value (mL/g)
• Location of vertical gradient calculations between
Figure 6-12
shallow/TZ unit and BR unit, showing value (+ is
downward gradient, - is upward gradient)
• Cross section maps showing ash position,
Figures 6-2 to 6-5
hydrostratigraphy, screen/open intervals, water
level, and
• Groundwater boron and COI concentrations (ug/L)
Figures 11-16 to
11-18
• Inset should show location (in plan view) of the
Figures 6-2 to 6 -
cross section
5, & 11-4 to 11-
63
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 2 of 13

2017 Comprehensive Site Assessment Update - Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 3 of 13
• Expectationr
.
Summary
Solid Phase properties for ash, fill, alluvium,
Tables 3-2, 3-3,
data tables:
soil/saprolite, deep, and bedrock units, as applicable,
6-1, to 6-3, 6-6 to
including:
6-11, & 6-19 to 6-
21
— Porosity
— Specific storage
— Permeability (field, lab, historic)
— Mineralogy and oxides
— Physical
Methodology, computations, etc. may be referenced, as
applicable
hydraulic conductivities (k, in ft/d), sorted by flow unit,
Tables 6-15 & 6 -
along with well identifier, flow unit, and screened/open
17
interval (ft bls)
sorption coefficients (Kd), sorted by COI then flow unit,
Table 13-1
along with boring location identifier, flow unit, and
depth (ft bls)
Raw data
• all GW, SW, and seep sample events (appendix and
Appendix B
tables showing
digital excel file)
chemistry
• all ash, soil, sediment, and whole rock chemistry
results for:
results (appendix and digital excel file)
• all SPLP samples (appendix and digital excel file)
• lat/long, flow unit (if applicable), etc. should be
included for each sample location
• current "master spreadsheet" format may be used
• lab QC data may be referenced if it has already been
provided in a separate report
Summary table of monitor well construction details
Table 2-1
showing well, location (decimal degree lat/long),
screen/open interval, depth to water, date installed,
flow unit being monitored, date abandoned if applicable,
etc.
• Water level measurements from all wells and current
Table 6-12
and historical measurement events (appendix and
digital excel file)
• List of wells that were dry during sampling or
measurement attempts, along with its flow unit,
screened/open interval, and date
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 3 of 13

2017 Comprehensive Site Assessment Update - Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations - Check List
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 4 of 13
•Report
Sorption coefficient testing - methodology, raw data,
Appendix G
and computations may be referenced
• Boring logs and well construction records
Appendix F
— Include all assessment, historic, CCR used for
CAMA, or other wells installed to date
— Each log should be quality controlled for accuracy
and include static WL information.
— Combined file Alpha -numeric sorting
Geophysical logs, rose diagrams, lineament map
Figure 6-13 & 6-
14
Soil and rock photos
Appendix F
Most recent pre -ash basin USGS topographic map, with
Figure 2-2 to 2-5
superimposed source areas
Screening level risk assessment
— Human health
Section 12.1
— Ecological
Section 12.2
Flow and transport model
Section 13.1
Geochemical model
Section 13.2
GW -SW mixing model, if applicable
Section 13.3
,,.,-
Overview of the major components, including source(s),
Sections 4, 6, 12,
hydrologic boundaries, migration pathway(s), receptors,
14
etc.
Regional geology and how it is affecting GW flow, GW
Section 5 & 14
quality, and contaminant transport at the site
Hydrostratigraphy (flow units)
• Flow properties and heterogeneities of each unit
Section 6.2.2
• Discuss hydraulic conductivities and vertical
Section 6.5 & 6.4
gradients (refer to maps in 4. above)
• Describe where flow units pinch out in each unit, as
Figures 6-2 to 6-5
applicable
• Discuss fractured bedrock heterogeneities across the
Sections 6.2.2,
site, including ranges of hydraulic conductivities and
6.5, & Table 6-13
porosities
to 6-19
• Discuss maximum depth of investigation and
Section 11.1 &
observed fracture density with depth; compare this
14.3
to the depths of proximate supply wells
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 4 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 5 of 13
•
..
• Areas of recharge and discharge (Include on vertical
Figure 6-12 &
7
gradient isocon figure)
Section 6.4
• Flow directions
_
Figures 6-6 to 6-
- Potentiometric map (summer) of shallow/TZ unit
11
— Potentiometric map (winter) of shallow/TZ unit
— Potentiometric map (summer) of bedrock unit
— Potentiometric map (winter) of bedrock unit
Potentiometric maps should utilize and show all
facility wells, should clearly show all blue line
tributaries, wetlands, and other SWs, and should
indicate areas where a flow unit pinches out as
applicable
Evaluation: Do seasonal or tidal influences affect Section 14.1
GW flow or GW chemistry?
- I 14 Ner. 1
Piper diagrams for shallow b/g, deep b/g, and bedrock Figures 10-1 to
b/g, along with well labels for plotted points 10-3
List PBTVs for soil
Table 7-2
List PBTVs for groundwater, by flow unit
Table 10-2
Methodology (appendix)
Appendix H
Description of background wells (why those chosen are
Section 10.1 &
appropriate for use) and soil sample locations
Appendix H
(appendix)
Table of all raw background data showing strikethroughs
Table 10-1 &
of unused high pH, high turbidity, autocorrelated, and
Appendix B
outlier data (appendix; digital excel file)
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 5 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations - Check List
• Expectations Report
For each source
History of ash placement
Section 3
area
Area, depth, and volume of ash (include also the area,
Section 3.1
depth, and volume of saturated/submerged ash)
Status of source removal or control
Section 2.8
Orthophoto base map (large scale, 1 inch - 100 feet)
Figures 2-1
showing waste boundary, compliance boundary if
applicable, 2 to 4 ft topographic contours, all blue line
surface water and wetland features, along with the
following:
- subset of supply well and SW receptors from 3.
Figures 2-1, 4-1,
above that are potentially susceptible to
4-2, & 4-3
contaminant migration from this particular source
area
- Include inset table with list of supply wells and
Figure 4-2 &
SW receptors for this source area
Table 4-3
- monitor wells, supply wells, and SW, seep, ash,
Figures 2-1, 2-10,
soil, and sediment locations
4-1, 4-2, 14-97 to
14-99
- Indicate most recent value (ug/L) for boron and
Figures 14-1 to
for each COI, and whether its concentration is
14-96
increasing, decreasing, stable, or unknown
Evaluation: Show a vertical gradient isopleth map
Figure 6-12,
and discuss vertical gradients and their effect on
Section 14.1
GW flow
List COIs (constituents above 02L/IMAC/background)
Section 10.2
for each flow unit beyond compliance boundary (or that
are within bedrock monitor wells within or beyond
compliance boundary if receptors are potentially at risk)
List pH and Eh ranges found in: pore water, d/g shallow
Figure 14-97
unit, d/g TZ unit, and d/g BR unit
Section 10.2
Evaluation: Explain the geochemical controls on
Sections 13.1 &
COIs that do not behave as a plume (Fe, Mn, etc.).
13.2
Evaluation: Use the pH, Eh, Kd, and HFO results to
Sections 13.1 &
discuss the expected capacity of the subsurface to
13.2
sorb cationic COIs and anionic COIs occurring
from source to receptor within each of the flow
units.
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 6 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
Key: Tables — Shaded Blue Figures — Shaded Green CAP — Shaded Red
Page 7 of 13
Expectations
ReportDEQ
Provide the
(a) have background concentrations been formally
Sections 7.1 and
following "data
established for all COIs in soil and groundwater?
10.1
inventory"
(b) for each source area, how many wells within each
Section 11.1
flow system are located along the contaminant plume
centerline? Along a cross sectional transect that is
perpendicular to the plume centerline?
(c) how many wells in (b) above are screened across
Section 11.1 and
the most contaminated vertical interval of a given flow
Figures 11-4 to
unit or are screened across the full thickness of the flow
11-63
unit?
(d) is the d/g edge of the plume centerline measured or
Section 11.1 and
is this location obstructed by a major SW or other
Figures 11-4 to
access issue? If so, is it measured by wells that are
11-63
screened across each flow unit?
(d) what is the length of record and how many valid
Section 10.0 &
sample events are available for wells listed in (b), (c),
Appendix B
and (d) above?
(e) does turbidity, well construction (for example, grout
Section 10.0 &
contamination, etc.), or well 'break in" issues preclude
Appendix B
the use of data in (b), (c), and or (d)?
(f) for each source area and within each flow unit, how
Sections 7 & 11,
many spatial locations were sampled for solid phase
Figure 14-99
chemistry and were these locations associated with 'pend
member" (maximum and minimum) groundwater
Section 11.2
concentrations for each contaminantE'J? How many of
these spatial locations are associated with (b) or (c)
above?
[1] Measuring the solid phase contaminant
concentrations in locations of both low and high
groundwater COI concentrations are important in
understanding the sorptive capacity of the system. This
is particularly true in the case of non-linear isotherm
adsorption models that describe most metals. That is, a
soil has a limited ability to sorb contaminant mass due,
for example, to limited sorption sites, so a soil can
become less efficient at removing mass at higher
dissolved concentrations.
(g) given that iron hydroxide (HFO) content is a good
Section 11.2,
indicator of retention capacity for most metal
Figure 14-99
contaminants, how many locations in (f) was HFO
measured?
Key: Tables — Shaded Blue Figures — Shaded Green CAP — Shaded Red
Page 7 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 8 of 13
Expectations
ReportDEQ
For each COI in
this particular
source area
Evaluation: Were wells properly positioned and
Section 11.1
screened to measure the horizontal and vertical
Figures 11-4 to
extent of the plume? If so, describe the horizontal
11-63
and vertical plume extent using plan view and
cross sectional maps.
Has the plume migrated to any supply wells, SW
Section 13.0
receptors, or GW future use areas?
Has the plume migrated to any supply wells, SW
Sections 13.0 &
receptors, or GW future use areas at concentrations
14.3
above 2L/IMAC/background?
Evaluation: Were wells positioned and screened
Section 11.1
to measure the maximum concentrations
migrating from source to receptor along the
longitudinal plume centerline? If so, describe the
plume characteristics in space and time as it flows
along the centerline, through the identified flow
units, and discharges into the nearest supply well
or SW receptor.
Evaluation: Use maps, graphs, statistics, and
Section 11.1,
mass movement or balance equations to show
13.1 & 15.2
whether the plume is expanding and whether the
plume is moving.
Show the COI -distance plot of wells positioned along a
Figures 6-2 to 6-5
plume centerline from source to farthest d/g location
& 11-1 to 11-63
(closest to receptor or future use area.
If applicable, show COI -distance plots at different
Section 13.1
timepoints to demonstrate potential plume expansion or
migration.
If applicable and sufficient sample events are available,
NA
use single -well linear regression or Mann-Kendall/Theil-
Sen type trend statistics to show increasing or
decreasing trends at selected d/g monitor wells.
Describe the soil -water pairs and Kd lab test sample
Figure 14-99,
results. Describe where they were collected, why those
Section 13.1.2
locations were selected, and whether those locations are
reflective of high and low COI concentrations in a given
flow unit.
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 8 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
Key: Tables — Shaded Blue Figures — Shaded Green CAP — Shaded Red
Page 9 of 13
•Report
Show concentration isopleths for each COI, including
Figures 10-5 to
contours of concentrations below and well above the
10-64
2L/IMAC (choose — five contours per COI, from
,'moderately low" to "high")
Show stacked boron -time plots of wells positioned along
Figures 14-17 to
a plume centerline from source to farthest d/g location
14-19
(closest to receptor)
Summary of corrective actions taken to date, if
Section 2.8
applicable
Describe preliminary corrective action alternatives for
Sections 15.3 &
this source area
15.4
• Description of model
Section 13
(Summary)
• Model construction — domain, layers, boundary
Section 13
conditions, recharge and discharge areas, supply
(Summary)
wells, hydraulic conductivities, stream conductances,
etc.
— Layer thicknesses in cross section (show vertical
scale in feet)
— Location of supply wells outside model domain
• Calibration method
To Be Provided in
CAP
— List of target wells used in calibration
— List of monitor wells not used in calibration and
the rationale for each that was omitted
• Calibration results (where mapped, superimpose on
To Be Provided in
orthophoto base map described above)
CAP
— Hydraulic conductivity zones versus measured
values for the zone
— List of simulated versus observed heads (include
wells and SW features)
— List of simulated versus observed vertical
gradients from well pair locations
— List of simulated versus observed discharge to
streams
— Potentiometric surface
■ Simulated for each flow layer
Key: Tables — Shaded Blue Figures — Shaded Green CAP — Shaded Red
Page 9 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 10 of 13
• Expectations
■ Observed, shallow
Report
■ Observed, deep
■ Observed, BR
— Flow paths (particle tracks) from each source
area
— Reverse flow paths (particle tracks) from SW
receptors
- Reverse flow paths (particle tracks) from supply
wells (because supply wells are usually open
from casing (at -50 to 75 ft) down to 200 to 500
feet, release particles in all simulated bedrock
layers)
• Quantitative sensitivity analyses to key inputs at
To Be Provided in
various selected d/g locations
CAP
• Describe the most significant model limitations
To Be Provided in
CAP
• Description of model
Section 13.1
Summar
• Model construction - boundary conditions, time
Section 13.1
steps, initial conditions, etc.
(Summary)
- Source loading, per layer
- Background concentrations, per layer
- Initial Kds, per layer
- Dispersivities, per layer
- Effective porosities, per layer
• Calibration method
Section 13.1
- List of target wells used in calibration
(Summary)
- List of monitor wells not used in calibration and
the rationale for each that was omitted
- Calibrated Kds, per layer
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 10 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
Key: Tables — Shaded Blue Figures — Shaded Green CAP — Shaded Red
Page 11 of 13
Expectations
ReportDEQ
To Be Provided in
• Calibration results (where mapped, superimpose on
orthophoto base map described above)
CAP
— List of simulated versus observed concentrations
in target wells
— List of simulated concentrations in SW discharge
locations as shown using particle tracks released
from source areas
— List of simulated versus observed concentrations
in selected well pair locations
• Boron isopleth map
To Be Provided in
— Simulated for each flow layer
CAP
— Observed, shallow
— Observed, deep
— Observed, BR
• For each source area, the time, direction, and
To Be Provided in
distance of contaminant travel must be predicted
CAP
under existing conditions and under any other
contemplated source control measure (for example,
engineered cap and (or) excavation). For these
scenarios, the following figures are expected:
— (a) a concentration -time plot for each COI
corresponding to the following locations: (i)
nearest supply well, (ii) nearest future
groundwater use area, and (iii) nearest surface
water.
■ In the plot margin, the following information
should be provided: the time it takes for the
COI to reach (i), (ii), and (iii), the time it
takes for the COI to reach (i), (ii), and (iii)
at its 2L/IMAC concentration, the time it
takes for the COI to reach (i), (ii), and (iii)
at its maximum concentration, and the time
it takes for the COI to reach (i), (ii), and (iii)
at a concentration that is back below the
2L/IMAC concentration.
— (b) a map superimposed on the requested base
map showing the maximum predicted migration
distance, at any detectable concentration, of
each COI.
— (c) a map superimposed on the requested base
map showing the maximum predicted migration
distance, at the 2L/IMAC standard concentration,
of each COI.
Key: Tables — Shaded Blue Figures — Shaded Green CAP — Shaded Red
Page 11 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations - Check List
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 12 of 13
1. • . .
.. 14L 'TiF.
• Quantitative sensitivity analyses to key inputs at
To Be Provid7dinvarious
selected d/g locations and times
CAP
• Describe the most significant model limitations
To Be Provid
CAP
10. Geochernicall
model•
• Conceptual model based on observed site data
Section 13.2
(Summary)
— Describe geochemical controls on COI levels in
each source area using site data
— Assumptions used in developing the model
— Discuss data used to develop the model
■ For example, how are mineral or adsorption
concentrations in fractured media converted
to PHREEQC concentrations representing
reaction along the fractures?
■ How were modeled reactive mineral
concentrations interpolated between or
extrapolated from the limited number of
data collected
— Discuss what the COI concentrations are most
sensitive to (pH, Eh, iron/aluminum oxide
content, Kd, distance from source, etc.)
— Describe the most significant limitations of the
model
• Numerical model (PHREEQC or PHREEQC 1-D
To Be Provided in
Transport model)
CAP
— Description of model
— Purpose of model
— Model construction
— Discuss data used to develop the flow model
— Results with comparison to observed well data
(PHREEQC model) or to longitudinal flow path
transect data (PHREEQC 1-D Transport model)
— Sensitivity analysis (to pH, Eh, Kd, COI
concentration, total dissolved ion content,
iron/aluminum oxide content, Kd, distance from
source, etc.)
- Describe the most significant limitations of the
model
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 12 of 13

2017 Comprehensive Site Assessment Update — Appendix A October 2017
Belews Creek Steam Station SynTerra
DEQ CSA Update Expectations — Check List
mom • Expectations Report
rPrGW-SW ,
mmml&nk
• Description of model
Section 13.3
(Summary)
• Purpose of model
Section 13.3
(Summary)
• Model construction
To Be Provided in
— Show on map the precise SW locations where
CAP
model output (simulated SW concentration) was
obtained
— List and discuss data used to construct model
■ Permitted effluent discharge concentrations
should be considered in the model
construction
— Assumptions
• Results
To Be Provided in
CAP
• Sensitivity analysis (to GW contaminant
To Be Provided in
concentrations, permitted effluent concentrations,
CAP
location where SW output was obtained, stream
flow, nearby effluent loading to the SW, etc.
• Describe the most significant limitations of the model
To Be Provided in
CAP
Key: Tables - Shaded Blue Figures - Shaded Green CAP - Shaded Red
Page 13 of 13

2017 Comprehensive Site Assessment Update October 2017
Belews Creek Steam Station
NDCENR NORR LETTER
(August 13, 2014)
SynTerra

A 4
A=(WA
4AF1
NCDENR
North Carolina Department of Environment and Natural Resources
Pat McCrory John E. Skvarla, III
Governor Secretary
August 13, 2014
CERTIFIED MAIL 7004 2510 0000 3651 1168
RETURN RECEIPT REQUESTED
Paul Newton
Duke Energy
526 South Church Street
Charlotte, NC 28202
Subject: Notice of Regulatory Requirements
Title 15A North Carolina Administrative Code (NCAC) 02L .0106
14 Coal Ash Facilities in North Carolina
Dear Mr. Newton:
Chapter 143, North Carolina General Statutes, authorizes and directs the Environmental
Management Commission of the Department of Environment and Natural Resources to protect
and preserve the water and air resources of the State. The Division of Water Resources (DWR)
has the delegated authority to enforce adopted pollution control rules.
Rule 15A NCAC 02L .0103(d) states that no person shall conduct or cause to be conducted any
activity which causes the concentration of any substance to exceed that specified in 15A NCAC
02L .0202. As of the date of this letter, exceedances of the groundwater quality standards at 15A
NCAC 02L .0200 Classifications and Water Quality Standards Applicable to the Groundwaters
of North Carolina have been reported at each of the subject coal ash facilities owned and
operated by Duke Energy (herein referred to as Duke).
Groundwater Assessment Plans
No later than September, 26 2014 Duke Energy shall submit to the Division of Water Resources
plans establishing proposed site assessment activities and schedules for the implementation,
completion, and submission of a comprehensive site assessment (CSA) report for each of the
following facilities in accordance with 15A NCAC 02L .0106(g):
Asheville Steam Electric Generating Plant
Belews Creek Steam Station
Buck Steam Station
Cape Fear Steam Electric Generating Plant
Cliffside Steam Station
1636 Mail Service Center, Raleigh, North Carolina 27699-1636
Phone: [phone] Internet: www.ncdenr.gov
An Equal Opportunity 1 Affirmative Action Employer— Made in part by recycled paper

Mr. Paul Newton
August 12, 2014
Page 2 of 3
Dan River Combined Cycle Station
H.F. Lee Steam Electric Plant
Marshall Steam Station
Mayo Steam Electric Generating Plant
Plant Allen Steam Station
Riverbend Steam Station
Roxboro Steam Electric Generating Plant
L.V. Sutton Electric Plant
Weatherspoon Steam Electric Plant
The site assessment plans shall include a description of the activities proposed to be completed
by Duke that are necessary to meet the requirements of 15A NCAC 02L .0106(g) and to provide
information concerning the following:
(1) the source and cause of contamination;
(2) any imminent hazards to public health and safety and actions taken to mitigate
them in accordance to 15A NCAC 02L .0106(f);
(3) all receptors, and significant exposure pathways;
(4) the horizontal and vertical extent of soil and groundwater contamination and all
significant factors affecting contaminant transport; and
(5) geological and hydrogeological features influencing the movement,. chemical, and
physical character of the contaminants.
For your convenience, we have attached guidelines detailing the information necessary for the
preparation of a CSA report. The DWR will review the plans and provide Duke with review
comments, either approving the plans or noting any deficiencies to be corrected, and a date by
which a corrected plan is to be submitted for further review and comment or approval. For those
facilities for which Duke has already submitted groundwater assessment plans, please update
your submittals to ensure they meet the requirements stated in this letter and referenced
attachments and submit them with the others.
Receptor Survey
No later than October 14th, 2104 as authorized pursuant to 15A NCAC 02L .0106(g), the DWR is
requesting that Duke perform a receptor survey at each of the subject facilities and submitted to
the DWR. The receptor survey is required by 15A NCAC 02L .0106(g) and shall include
identification of all receptors within a radius of 2,640 feet (one-half mile) from the established
compliance boundary identified in the respective National Pollutant Discharge Elimination
System (NPDES) permits. Receptors shall include, but shall not be limited to, public and private
water supply wells (including irrigation wells and unused or abandoned wells) and surface water
features within one-half mile of the facility compliance boundary. For those facilities for which
Duke has already submitted a receptor survey, please update your submittals to ensure they meet
the requirements stated in this letter and referenced attachments and submit them with the others.
If they do not meet these requirements, you must modify and resubmit the plans.

Mr. Paul Newton
August 12, 2014
Page 3 of 3
The results of the receptor survey shall be presented on a sufficiently scaled map. The map shall
show the coal ash facility location, the facility property boundary, the waste and compliance
boundaries, and all monitoring wells listed in the respective NPDES permits. Any identified
water supply wells shall be located on the map and shall have the well owner's name and
location address listed on a separate table that can be matched to its location on the map.
Failure to comply with the State's rules in the manner and time specified may result in the
assessment of civil penalties and/or the use of other enforcement mechanisms available to the
State.
We appreciate your attention and prompt response in this matter. If you have any questions,
please feel free to contact S. Jay Zimmerman, Water Quality Regional Operations Section Chief,
at [phone].
2hn
ierely,
E. Skvarla, III
Attachment enclosed
cc: Thomas A. Reeder, Director, Division of Water Resources
Regional Offices — WQROS
File Copy

2017 Comprehensive Site Assessment Update October 2017
Belews Creek Steam Station
SynTerra
REVISED INTERIM MONITORING NETWORK
(October 19, 2017)

Water Resources
Environmental Quality
October 19, 2017
Paul Draovitch
Senior Vice President
Environmental, Health & Safety
Duke Energy
526 South Church Street
Mail Code EC3XP
Charlotte, North Carolina 28202
Subject: Revised Interim Monitoring Plans for 14 Duke Energy Facilities
Fourth Quarter 2017
Dear Mr. Draovitch:
ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. JAY ZIMMERMAN
Director
The North Carolina Department of Environmental Quality (DEQ) is providing the attached revised
Interim Monitoring Plans (IMPs) for the respective coal ash facilities. Per our agreement, the DEQ
will be providing Duke Energy with updated IMPs quarterly until the individual facility Corrective
Action Plans are approved. Also, per our agreement, Duke Energy will include and begin sampling
any newly installed groundwater assessment wells as part of the facility IMP and the DEQ will
formally include it in the subsequent updated quarterly IMP.
The attached IMPs only contain references to groundwater monitoring locations. Sampling at
surface water locations that were identified as part of the May 1, 2017 communication from DEQ
to Duke Energy regarding revised IMPs at the facilities is expected to continue pending further
notice. DEQ may elect to provide Duke Energy with additional surface sampling locations to
incorporate into the revised IMPs at a future time. For clarification, we have also provided the
minimum expected groundwater sampling analyte list.
The attached revised facility IMPs shall be conducted on a quarterly basis commencing the fourth
quarter of calendar year 2017 pursuant to 15A NCAC 02L .0 110, until Corrective Action Plans
are accepted for the individual facilities or as directed otherwise by the DEQ. The quarterly
sampling events will be conducted in conjunction with planned compliance monitoring sampling
events for three quarters during the calendar year, supplemented with an additional sampling event
conducted at each facility in order to provide four rounds of monitoring data to evaluate seasonal
fluctuations during a year-long timeframe. If sampling an individual groundwater location is
problematic, please call the Regional Office that manages the facility to discuss issues. Any
changes to IMPs and sampling requirements must be discussed with the respective Regional
Offices and coordinated by official correspondence from the DEQ Central Office.
Since Duke Energy will submit updated Comprehensive Site Assessments in the near future, the
requirement for an annual monitoring report submitted by April 30th for each respective coal
State of North Carolina I Environmental Quality I Division of Water Resources
Water Quality Regional Operations Section
1636 Mail Service Center I Raleigh, North Carolina 27699-1636
919-707-9129

facility as set forth in the May 1, 2017 letter will be extended to a date in 2018 that will be later
defined.
In order to optimize the groundwater monitoring at each facility, DEQ will be removing the
groundwater monitoring condition from the NPDES permits as they are reissued. Duke Energy
shall continue to monitor the compliance wells separately under the individual NPDES permits
until the NPDES permits are reissued with no groundwater monitoring condition. At that time,
the compliance wells shall continue to be monitored per the attached revised IMPs under the
authority of 15A NCAC 02L.0110.
The DEQ is open to consider further optimization of the IMPS following a qualitative and
quantitative review of site-specific data. A thorough analysis of spatial and temporal trends related
to contaminant distribution that include determination of background conditions and identification
of areas impacted by coal ash residuals must be provided as a decision framework to support
improvements to long-term monitoring programs.
If you have any questions, please feel free to contact Steve Lanter at [phone].
Sincerely,
S. Jay Zimmerman, P.G., Director
Division of Water Resources
Attachments: Revised Interim Monitoring Plans for the 14 coal ash facilities
cc: WQROS Regional Offices
WQROS Central File Copy

Revised Allen Steam Station Interim Monitoring Plan — Groundwater Only
Wells to be Sampled
Sample for
Radionuclides
(X
Regional Office Notes
AB -10D
AB -10S
AB -11D
X
AB -12D
AB -12S
AB -13D
X
AB -13S
X
AB-14BR
AB -14D
AB -1R
AB -2
AB -20D
AB -20S
AB-21BRL
X
AB -21D
X
Sample to be analyzed for total boron and sulfate
only.
AB -21 S
X
AB -21 SL
X
AB-22BR
Lower bedrock (AB-22BRL) scheduled to be
installed by mid-October — early November for
purposes of vertical delineation.
AB -22D
AB -22S
AB-23BRU
Sample to be analyzed for total boron and sulfate
only.
AB -23S
AB-24BR
AB -24D
Sample to be analyzed for total boron and sulfate
only.
AB -24S
AB-24SL
AB-25BR
X
Sample to be analyzed for total boron and sulfate
only.
AB-25BRU
X
Sample to be analyzed for total boron and sulfate
only.
AB -25S
X
AB-25SL
X
AB -26S
AB-27BR
Allen Steam Station Page 1 of 4 October 1, 2017

AB -27D
AB -27S
AB -28D
AB -28S
AB -29D
AB -29S
AB-29SL
AB -2D
AB -30D
AB -30S
AB -31 S
AB -32D
AB -32S
AB -33D
X
AB -33S
X
AB -34D
AB -34S
AB-35BR
X
AB -35D
X
Sample to be analyzed for total boron and sulfate
only.
AB -35S
X
AB -36D
AB -36S
AB -37D
AB -37S
AB-38BR
AB -38D
AB -38S
AB -39D
AB -39S
AB -413R
X
AB -4D
X
AB -4S
X
AB -5
AB -6A
X
AB -6R
X
AB -9D
X
AB -9S
X
BG-lDA
X
Note: BG -1D has been abandoned and thus
removed from the IMP. BG-lDA was installed as
replacement well.
BG -1S
X
Allen Steam Station Page 2 of 4 October 1, 2017

BG-2BRA
X
Note: BG-2BR has been abandoned and thus
removed from the IMP. BG-2BRA was installed as
replacement well.
BG -2D
X
BG -2S
X
BG -3D
BG -3S
BG-4BR
BG -4D
BG -4S
GWA-14DA
Note: GWA-14D has been abandoned and thus
removed from the IMP. GWA-14DA was installed
as replacement well.
GWA-14S
GWA-15D
GWA-15S
GWA-16D
GWA-16S
GWA-17D
X
GWA-17S
X
GWA-18D
GWA-18S
GWA-19D
Sample to be analyzed for total boron and sulfate
only.
GWA-19S
GWA-IBR
X
GWA-1D
X
GWA-1S
X
GWA-21BR
X
GWA-21DA
X
Note: GWA-21D has been abandoned and thus
removed from the IMP. GWA-21DA was installed
as replacement well.
GWA-21S
X
GWA-22D
GWA-22S
GWA-23D
Sample to be analyzed for total boron and sulfate
only.
GWA-23S
GWA-24BR
GWA-24D
GWA-24SA
Note: GWA-24S has been abandoned and thus
removed from the IMP. GWA-24SA was installed
as replacement well.
GWA-26D
Allen Steam Station Page 3 of October 1, 2017

GWA-26S
Boron
Copper
GWA-2D
X
Thallium
GWA-2S
X
Hexavalent
GWA-3BRA
X
Note: GWA-3BR has been abandoned and thus
removed from the IMP. GWA-3BRA was installed
as replacement well.
GWA-3D
X
Chromium
GWA-3S
X
Carbon
GWA-4BRA
X
Note: GWA-4BR has been abandoned and thus
removed from the IMP. GWA-4BRA was installed
as replacement well.
GWA-4D
X
Total
GWA-4S
X
Iron
GWA-SBRA
X
Note: GWA-5BR has been abandoned and thus
removed from the IMP. GWA-SBRA was installed
as replacement well.
GWA-5D
X
GWA-5S
X
Uranium
GWA-6BR
X
Replacement bedrock (GWA-6BRA) scheduled to
be installed by mid-October — early November.
GWA-6DA
X
Total
GWA-6S
X
Lead
GWA-7D
X
Suspended
GWA-7S
X
GWA-8D
Solids
GWA-8S
Chromium
Magnesium
GWA-9D
X
Vanadium
GWA-9S
X
GWA-9BR
X
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Allen Steam Station Page 4 of 4 October 1, 2017

Revised Asheville Steam Electric Plant Interim Monitoring Plan — Groundwater Onlv
Wells to be
Sampled
Sample for
Radionuclides
X
Regional Office Notes
ABMW-I1BR
AMW-03B
X
AMW-1B
X
AMW-2A
AMW-213
water level only
APZ-30
water level only
B-1
water level only
B -1-A
water level only
B-2
water level only
CB -1
X
CB -IBR
water level only
CB-1BRL
water level only
CB -1D
X
CB-8BR
X
CB -8D
water level only
CB-9BR
X
CB-9SL
X
GW-lBR
GW -1D
GW -2
X
GW -3
X
GW -4
X
GW -5
X
MW -3D
X
MW-5BR
MW -5D
MW -8S
X
MW -10
X
MW -11
MW -111)
MW-13BR
MW -13D
MW-14BR
MW -15A
X
MW-15BR
water level only
MW -15D
X
MW -16A
X
Asheville Steam Electric Plant Page 1 of 3 October 1, 2017

MW-16BR
X
MW -17A
X
MW-18BR
X
MW-18BRL
X
MW -18D
X
MW-19BR
water level only
MW -20A
MW -21D
X
MW-22BR
X
MW -22D
X
MW-23BR
MW-23DL
MW-23DU
MW -24S
X
MW-6BR
X
MW -6D
X
MW -6S
X
MW-7BR
water level only
MW-8BR
MW-9BR
X
MW -9D
X
MW -9S
X
P-102
water level only
P-103
PZ -16
Needs to be replaced and added to IMP.
PZ -17D
X
PZ -17S
X
PZ -19
X
PZ -22
X
Asheville Steam Electric Plant Page 2 of 3 October 1, 2017

Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Asheville Steam Electric Plant Page 3 of 3 October 1, 2017

Revised Belews Creek Steam Station Interim Monitoring Plan — Groundwater Onlv
Wells to be
Sampled
Sample for
Radionuclides
(X)
Regional Office Notes
AB -IBR
AB -1D
AB -IS
AB -2D
AB -2S
AB -3D
AB -3S
AB-4BR
Measure pH, if still high, do not sample
AB-4BRD
AB -4D
AB -4S
AB4SL
Measure pH, if still high, do not sample
AB -5D
AB -5S
AB-5SL
AB -6D
AB -6S
AB-6SL
AB -7D
AB -7S
AB -8D
AB -8S
AB-8SL
AB -913R
AB-9BRD
AB -9D
AB -9S
BG -1D
BG -IS
X
Dry 7/19/17; continue monitoring
BG-2BR
BG -2D
X
BG -2S
X
BG -3D
BG -3S
GWA-10DA
GWA-10S
GWA-11D
Belews Creek Steam Station Page 1 of 4 October 1, 2017

GWA-11S
GWA-12BR
GWA-12D
GWA-12S
GWA-16BR
GWA-16DA
GWA-16S
GWA-17D
GWA-17S
GWA-18D
GWA-18SA
GWA-19BR
GWA-19D
GWA-19SA
GWA-IBR
X
GWA-1D
X
GWA-1S
X
GWA-20BR
GWA-20D
GWA-20SA
GWA-21 D
GWA-21S
GWA-22D
GWA-22S
GWA-23D
GWA-23S
GWA-24BR
GWA-24D
X
GWA-24S
X
Insufficient Volume 7/21/17; continue monitoring
GWA-25BR
X
GWA-26BR
X
GWA-26D
X
GWA-26S
X
GWA-27BR
GWA-27D
GWA-27S
GWA-2D
GWA-2S
GWA-30D
X
GWA-30S
X
GWA-31D
Belews Creek Steam Station Page 2 of 4 October 1, 2017

GWA-31S
GWA-32D
GWA-32S
GWA-3D
GWA-3S
Insufficient Volume 7/21/17; continue monitoring
GWA-6D
X
GWA-6S
X
GWA-7D
X
GWA-7SA
X
GWA-8D
X
GWA-8S
X
GWA-9BR
GWA-9D
GWA-9S
MW-104BR
MW -104D
MW -104S
MW-200BR
X
MW -200D
X
MW -200S
X
MW-201BR
MW -201D
MW-202BR
MW -202D
MW -202S
MW-203BR
MW -203D
MW -2035
MW -204D
MW -204S
MW -3
X
Belews Creek Steam Station Page 3 of 4 October 1, 2017

Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Belews Creek Steam Station Page 4 of 4 October 1, 2017

Revised Buck Combined Cycle Station Interim Monitoring Plan — Groundwater Only
Wells to be
Sampled
Sample for
Radionuclides
X
Regional Office Notes
AB -1D
AB -1 OBR
Lower bedrock (AB -1 OBRL) scheduled to be installed
by early November — early December for purposes of
vertical delineation.
AB -101)
AB -10S
AB-2BR
X
Sample to be analyzed for total boron and sulfate
only.
AB -2D
X
AB -2S
X
AB-2SL
X
AB -3D
AB -3S
AB-4BR
Discontinue sampling AB-4BR. Based on review of
analytical (submitted on 2/13/2017), water quality at
AB-4BRL is acceptable (pending background).
AB-4BRL
AB-4BRU
AB -4S
AB-4SL
AB-SBRU
X
AB -5S
X
AB-5SL
X
AB-6BRU
AB-7BRU
AB -7S
AB-8BRU
AB -8S
AB-9BRA
X
Note: AB-9BR has been abandoned and thus removed
from the IMP. AB-9BRA was installed as
re lacement well.
AB-9BRUA
X
Note: AB-9BRU has been abandoned and thus
removed from the IMP. AB-9BRUA was installed as
replacement well.
AB -9S
X
AS -1D
AS -1S
AS -2D
AS -3D
Buck Combined Cycle Station Page I of 4 October 1, 2017

AS -3S
BG-1BRA
Note: BG-lBR has been abandoned and thus removed
from the IMP. BG-1BRA was installed as
replacement well.
BG -IDA
Note: BG -1D has been abandoned and thus removed
from the IMP. BG -IDA was installed as replacement
well.
BG -IS
BG -2D
X
BG -2S
X
BG-3BRU
X
BG -3S
X
GWA-10D
GWA-10S
GWA-11D
GWA-11S
GWA-12BRU
X
GWA-12S
X
GWA-13D
GWA-13SR
GWA-14BR
X
GWA-14D
X
Sample to be analyzed for total boron and sulfate
only.
GWA-14S
X
GWA-15D
X
GWA-15BR scheduled to be installed early
November — early December for purposes of vertical
delineation.
GWA-15S
X
GWA-16BR
X
GWA-16D
X
GWA-16S
X
GWA-17S
GWA-18DA
X
Note: GWA-18D has been abandoned and thus
removed from the IMP. GWA-I BDA was installed as
replacement well.
GWA-18S
X
GWA-19D
X
GWA-19S
X
GWA-1D
X
GWA-1 S
X
GWA-20D
X
GWA-20S
X
GWA-22D
X
Buck Combined Cycle Station Page 2 of 4 October 1, 2017

GWA-2BRA
X
Note: GWA-2BR has been abandoned and thus
removed from the IMP. GWA-2BRA was installed as
replacement well.
GWA-2BRU
X
GWA-2S
X
GWA-3BR
X
GWA-3BRU
X
GWA-3S
X
GWA-4D
X
GWA-4S
X
GWA-SBRU
X
GWA-5S
X
GWA-6BR
X
Lower bedrock (GWA-6BRL) scheduled to be
installed by early November — early December for
oses of vertical delineation.
GWA-6BRU
X
GWA-6S
X
GWA-7D
X
GWA-7S
X
GWA-8D
GWA-9BRA
X
Note: GWA-9BR has been abandoned and thus
removed from the IMP. GWA-9BRA was installed as
replacement well.
GWA-9D
X
GWA-9S
X
MW -101)
MW -11 BR
X
Lower bedrock (MW-11BRL) scheduled to be
installed by early November — early December for
purposes of vertical delineation.
MW -11D
X
MW-llS
X
MW -12D
MW -12S
MW -13D
MW -ID
MW -1S
MW -2S
MW -2D
MW -3D
X
MW -3S
X
MW -4D
MW -4S
MW -5D
Buck Combined Cycle Station Page 3 of 4 October 1, 2017

MW -5S
Boron
Copper
MW-6BR
X
Thallium
MW -6D
X
Hexavalent
MW -6S
X
Total Organic
MW -7D
Chromium
MW -7S
Carbon
MW-8BR
X
Note: MW-8BR has been abandoned and thus
removed from the IMP. MW-8BRA was installed as
replacement well.
MW -8D
X
Total
MW -8S
X
Iron
MW -9D
X
Combined
MW -9S
X
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Buck Combined Cycle Station Page 4 of 4 October 1, 2017

Revised Cane Fear Steam Electric Plant Interim Monitoring Plan — Groundwater Only
Wells to be
Sampled
Sample for
Radionuclides
(X
Regional Office Notes
ABMW-1
X
ABMW-IBR
X
ABMW-1S
X
ABMW-2SL
ABMW-2SU
ABMW-3
X
ABMW-3BR
ABMW-3SR
X
ABMW-4
X
ABMW-4S
X
ABMW-5BR
ABMW-5S
BGMW-4
X
BGTMW-4
X
CMW-01
X
CMW-02
CMW-03
X
CMW-5R
Installed 7/19/17
CMW-06
X
CMW-07
X
CMW-08
X
CTMW-01
X
CTMW-02
CTMW-07
CTMW-08
X
MW -10
X
MW -1013R
X
MW -1 OBRL
MW -101)
MW -11
X
MW -12
X
MW-12BR
MW -13
MW-15BR
X
MW-15SL
X
MW-15SU
X
MW-16BR
X
Cape Fear Steam Electric Plant Page 1 of 3 October 1, 2017

MW -16S
X
MW-17BR
MW-17SL
X
MW-17SU
X
MW -18S
X
MW -19S
MW-20BR
MW -20S
MW-21BR
MW -21 SL
X
MW-21SU
X
MW-22BR
MW -22S
MW-23BR
MW -23D
X
MW -23S
X
MW-24BR
X
Duke indicated in email sent 9-18-17 this well
location is designated MW-24BR
MW -24S
X
MW-5BRR
MW-6BR
X
MW -9
X
MW-9BR
X
PZ -1
PZ -10
PZ -2
PZ -3D
PZ -3S
PZ -4
PZ -5
X
PZ -6
PZ -7
PZ -8
Cape Fear Steam Electric Plant Page 2 of 3 October 1, 2017

Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Cape Fear Steam Electric Plant Page 3 of 3 October 1, 2017

Revised James E. Rogers Energy Complex Interim Monitoring Plan — Groundwater Only
Wells to be
Sampled
Sample for
Radionuclides
M
Regional Office Notes
AB -1D
AB -1S
AB -2D
AB -2S
AB-3BR
A13 -3I
AB -3S
X
AB-3SL
X
AB-4BR
AB -4D
AB -4S
X
AB-4SL
X
AB-5BR
AB-5BRU
AB -5S
X
AB-6BR
AB -6D
AB -6S
X
AS -1D
AS -1 SB
AS-2BR
AS -2D
X
AS -2S
X
AS-3BRU
AS -4D
AS -4S
AS-5BRU
AS -5S
AS -6D
AS -6S
AS -7D
AS -7S
X
BG -1D
X
BG -1S
X
BG -2D
X
CCPMW-1D
X
CCPMW-1S
X
James E. Rogers Energy Complex Page 1 of 5 October 1, 2017

CLMW-1
X
CLMW-2
CLMW-3D
X
CLMW-3S
X
CLMW-5D
CLMW-5S
CLMW-6
CLP-1
water level only
CLP-2
water level only
GWA-10D
GWA-10S
GWA-11BRU
X
GWA-11S
X
GWA-12BRU
GWA-12S
GWA-13BR
GWA-14BR
GWA-14D
GWA-14S
GWA-1BRU
GWA-20BR
X
GWA-20D
X
GWA-20S
X
GWA-21BR
X
GWA-21BRU
X
GWA-21D
GWA-21S
X
GWA-22D
GWA-22S
X
GWA-23D
GWA-24BR
GWA-24D
GWA-24S
GWA-25S
GWA-25D
water level only
GWA-26S
GWA-26D
water level only
GWA-27BR
X
GWA-27D-A
X
GWA-28BR
GWA-28BRU
James E. Rogers Energy Complex Page 2 of 5 October 1, 2017

GWA-28S
GWA-29D
X
GWA-2BR
X
GWA-2BRU
X
GWA-2S
X
GWA-30BR
GWA-30BRU
water level only
GWA-30S
GWA-31BR-A
GWA-31D
GWA-32D
GWA-32BR
water level only
GWA-33BR
GWA-33D
GWA-33S
GWA-34S
GWA-35D
GWA-35S
GWA-36D
X
GWA-36S
X
GWA-37D
GWA-37S
GWA-38D
GWA-38S
GWA-39S
water level only
GWA-3D
X
GWA-40S
water level only
GWA-42S
water level only
GWA-43D
GWA-43S
GWA-44BR
GWA-44D
GWA-44S
GWA-45D
GWA-45S
GWA-46D
GWA-47D
GWA-48BR
GWA-48S
GWA-4D
X
GWA-4S
X
James E. Rogers Energy Complex Page 3 of 5 October 1, 2017

GWA-SBRU
GWA-5S
GWA-6S
GWA-6D
water level only
1B-3D
IB-3S
X
MW-10D
MW-10S
MW-11D
MW-11S
X
MW-20D
MW-20DR
MW-21BR
MW-21D
MW-22BR
MW-22DR
MW-23D
MW-23DR
MW-23S
MW-24D
X
MW-24DR
X
MW-25DR
MW-2D-A
MW-30D
X
MW-30S
X
MW-32BR
X
MW-32D
X
MW-32S
X
MW-34S
MW-34BRU
MW-36BRU
MW-36S
MW-38BR
X
MW-38D
X
MW-38S
X
MW-40BRU
MW-40S
MW-42D
MW-42S
MW-8D
MW-8S
X
James E. Rogers Energy Complex Page 4 of 5 October 1, 2017

U5 -1D
Boron
Cop er
U5-1 S
Selenium
Thallium
U5-2BR
Cadmium
Hexavalent
U5 -2D
X
Total Organic
U5 -2S -SL -A
X
Chromium
U5 -3D
Carbon
U5 -4D
U5 -4S
Total
U5-5BR
Calcium
Iron
U5 -5D
X
Combined
U5 -6D
U5 -6S
Uranium
U5-8BR
U5 -8D
Total
U5 -8S
Chloride
Lead
Minimum Parameters to be Analyzed
Aluminum
Boron
Cop er
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
James E. Rogers Energy Complex Page 5 of 5 October 1, 2017

Revised Dan River Combined Cycle Station Interim Monitoring Plan — Groundwater Only
Wells to be Sampled
Sample for
Radionuclides
X
Regional Office Notes
AB-30BR
AB -30D
AB -30S
AB-35BR
AB -5D
AB -5S
AS -12S
AS -813R
AS -8D
BG -IDA
X
Insufficient volume 8/24/17; continue motoring
BG -101)
X
BG -10S
X
BG -1013R
X
BG -5D
BG -5S
GWA-10D
GWA-12D
GWA-12S
GWA-14D
GWA-14S
GWA-15D
GWA-16D
GWA-16S
GWA-17D
GWA-18D
X
GWA-20D
GWA-20S
GWA-4D
GWA-4S
GWA-513R
GWA-5BRD
GWA-6D
X
GWA-6S
X
GWA-7D
GWA-7S
GWA-8BR
GWA-8D
Dan River Combined Cycle Station Page 1 of 2 October 1, 2017

GWA-8S
Boron
Copper
GWA-9D
X
Thallium
GWA-9S
X
Hexavalent
MW -10
X
Dry 8/24/17; continue monitoring
MW -10D
X
Chromium
MW -11
X
Dry 8/24/17; continue monitoring
MW -11D
X
MW -12
X
Total
MW -12D
X
Iron
MW -21D
Strontium
Combined
MW -21S
MW-22BR
X
Uranium
MW -22D
X
MW -22S
X
Total
MW-23BR
Chloride
Lead
MW -231)
Sulfate
Suspended
MW-317BR
MW-317BRL
Solids
MW -9
Chromium
Dry 8/24/17; continue monitoring
MW -91)
Sulfide
Vanadium
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Dan River Combined Cycle Station Page 2 of 2 October 1, 2017

Revised H. F. Lee Energy Complex Interim Monitoring Plan — Groundwater Onlv
Wells to be
Sampled
Sample for
Radionuclides
X
Regional Office Notes
ABMW-1
ABMW-1S
X
AMW-11BC
AMW-11S
X
AMW-12BC
AMW-12S
AMW-13BC
AMW-13S
AMW-14BC
AMW-14S
AMW-15BC
AMW-15S
AMW-16BC
AMw-17BC
AMW-17S
AMW-18S
X
AMW-6RBC
AMW-913C
AMW-19S
Well pairs AMW-19-23 SBC were added to the list.
AMW-19BC
AMW-20S
AMW-20BC
AMW-21 S
AMW-21BC
AMW-22S
AMW-22BC
AMW-23S
AMW-23BC
BGMW-10
BGMW-9
BW -1
CCR -100S
X
CMW-10
CMW-5
CMW-6R
CMW-7
CMW-8
H. F. Lee Energy Complex Page 1 of 3 October 1, 2017

CTMW-1
CW-1
CW-2
CW-3
CW-4
DMW-1
DMW-2
DMW-3
IABMW-1
IABMW-1S
X
IABMW-2S
IA13MW-3
IABMW-3S
X
IMW-04BC
IMW-05BC
IMW-lBC
IMW-1S
X
RAW-2BC
IMW-3BC
IMW-3S
X
MW-4S
X
IMW-5S
X
LLMW-1
LLM W-1 S
LLMW-2
LLMW-2S
MW-1
MW-2
MW-3
X
SMW-3
SMW-4
SMW-5
H. F. Lee Energy Complex Page 2 of 3 October 1, 2017

Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
H. F. Lee Energy Complex Page 3 of 3 October 1, 2017

Revised Marshall Steam Station Interim Monitoring Plan — Groundwater Only
Wells to be Sampled
Sample for
Radionuclides
X
Regional Office Notes
AB-10BR
AB -1O1)
AB -10S
AB -1 OSL
AB -111)
AB -IIS
AB-12BR
X
AB -12D
X
AB -12S
X
AB-12SL
X
AB -13D
AB -13S
AB -14D
AB -14S
AB-15BR
AB -15D
AB -15S
AB-15SL
AB -16D
AB -16S
AB -17D
AB -17S
AB -18D
AB -18S
AB -IBR
X
Lower bedrock (AB-1BRL) scheduled to be
installed by mid-October for purposes of vertical
delineation.
AB -1D
X
AB -IS
X
AB -20D
AB -20S
AB -21D
AB -21S
AB -21)
X
AB -2S
X
AB -3D
AB -3S
AB -41)
Marshall Steam Station Page I of 5 October 1, 2017

AB -4S
AB-4SL
AB-5BR
X
AB -5D
X
AB -5S
X
AB-6BRA
Lower bedrock (AB-6BRL) scheduled to be
installed by mid-October for purposes of vertical
delineation.
Note: AB-6BR has been abandoned and thus
removed from the IMP. AB-6BRA was installed
as replacement well.
AB -6D
AB -6S
AB -7D
AB -7S
AB -8D
AB -8S
AB-9BR
AB -9D
AB -9S
AL -IBR
X
AL -1D
X
AL -IS
X
AL-2BR
AL-2BRL
Lower bedrock (AL-2BRLL) scheduled to be
installed by mid-October for purposes of vertical
delineation.
AL -2D
AL -2S
AL -313R
AL -3D
AL -3S
AL-4BR
Lower bedrock (AL-4BRL) scheduled to be
installed by mid-October for purposes of vertical
delineation.
AL -4D
BG-1BRA
X
Note: BG-lBR has been abandoned and thus
removed from the IMP. BG-1BRA was installed
as replacement well.
BG -1D
X
BG -IS
X
BG-2BR
X
BG -2S
X
Marshall Steam Station Page 2 of 5 October 1, 2017

BG-3BR
X
BG-3D
X
BG-3S
X
GWA-lBR
X
GWA-1D
X
GWA-1S
X
GWA-2DA
Note: GWA-2D has been abandoned and thus
removed from the IMP. GWA-2DA was
installed as replacement well.
GWA-2S
GWA-3D
GWA-3S
GWA-4D
GWA-4S
GWA-5D
GWA-5S
GWA-6D
X
GWA-6S
X
GWA-7D
GWA-7S
GWA-8D
GWA-8S
GWA-9BR
GWA-10D
GWA-10S
GWA-11BR
X
GWA-11D
X
GWA-11 S
X
GWA-12BR
X
GWA-12D
Sample to be analyzed for total boron and sulfate
only.
GWA-12S
X
GWA-13DA
Sample to be analyzed for total boron and sulfate
only.
GWA-13S
GWA-14D
GWA-14S
GWA-15S
X
MS-8
MS-10
X
MS-11
MS-13
Marshall Steam Station Page 3 of 5 October 1, 2017

MW -1
MW -101)
X
MW-lOS
X
MW -111)
MW-llS
MW -12D
MW -12S
MW -13D
MW -13S
MW-14BR
X
MW -14D
X
MW -14S
X
MW -2
MW -3
MW -4
X
MW -4D
X
MW -5
MW -6D
X
MW -6S
X
MW -7
Water level only
MW -7D
X
MW -7S
X
MW -8D
X
MW -8S
X
MW -9D
X
MW -9S
X
OB -1 (Dry Ash Basin)
OB -1 (Dry Ash Landfill)
Water level only
Marshall Steam Station Page 4 of 5 October 1, 2017

Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium.
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Marshall Steam Station Page 5 of 5 October 1, 2017

Revised Mayo Steam Electric Plant Interim Monitoring Plan — Groundwater Only
Wells to be Sampled
Sample for
Radionuclides
Regional Office Notes
ABMW-1
X
ABMW-2
ABMW-2BR
ABMW-2BRL
ABMW-3
ABMW-3S
ABMW-4
X
ABMW-4BR
ABMW-4D
BG -I
X
BG -2
X
CW -1
CW -1D
CW -2
X
CW -2D
X
CW -3
CW -4
CW -5
CW -6
X
MW -1013R
X
MW-11BR
water level only
MW -12D
X
MW -12S
X
MW-13BR
MW-14BR
MW-15BR
water level only
MW-16BR
X
MW -16D
X
MW -16S
MW -18D
New installation
MW-18BR
New installation
MW -19D
New installation
MW-19BR
New installation
MW -2
MW -3
X
MW-3BR
MW -4
Mayo Steam Electric Plant Pagel of 2 October 1, 2017

MW-5BR
MW-8BR
MW-9BR water level only
MW-9BRL
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Mayo Steam Electric Plant Page 2 of 2 October 1, 2017

Revised Riverbend Steam Station Interim Monitoring Plan — Groundwater Only
Wells to be
Sampled
Sample for
Radionuclides
X
Regional Office Notes
AB -1D
Measure pH, if still >10, not sample.
AB -IS
AB -2D
AB -2S
AB -8D
AB -8S
BG -IDA
BG -IS
BG-2BR
BG -2D
BG -2S
BG -3D
BG -3S
BG-4BR
X
BG -4D
X
BG -4S
X
BG-5BR
BG -5D
C-1BRUA
C-1 S
C -2D
C -2S
GWA-10BRU
Measure pH, if still >10, not sample.
GWA-10S
GWA-11D
GWA-11 S
GWA-12D
X
GWA-12S
X
GWA-13D
GWA-13S
GWA-14D
GWA-14S
GWA-15D
GWA-15S
X
GWA-1BRU
GWA-1 S
GWA-20BR
Measure pH, if still >10, not sample.
Riverbend Steam Station Page I of 3 October 1, 2017

GWA-20DA
GWA-20S
GWA-21BR
GWA-21D
GWA-21 S
GWA-22BR-A
X
GWA-22D
X
GWA-22S
X
GWA-23BR
Measure pH, if still >10, not sample.
GWA-23DA
GWA-23S
GWA-2BR
X
GWA-2BRU
X
Measure pH, if still >10, not sample.
GWA-2S
X
GWA-3BR
GWA-3D
GWA-3S-A
GWA-4BR
Measure pH, if still >10, not sample.
GWA-4D
X
GWA-4S
X
GWA-5D
GWA-5S
GWA-6D
X
Measure pH, if still >10, not sample.
GWA-6S
X
GWA-7BR
GWA-7D
GWA-7S
GWA-8D
X
GWA-8S
X
GWA-9BR
X
GWA-9D
X
GWA-9S
X
MW-10
X
MW-11DR
MW-11 SR
MW-13
MW-14
X
MW-15
MW-15BR
MW-15DA
MW-1D
Riverbend Steam Station Page 2 of 3 October 1, 2017

MW -1S
Boron
Copper
MW -2D
Selenium
Thallium
MW -2S -A
Cadmium
Hexavalent
MW -3D
Sodium
Total Organic
MW -3S
Chromium
MW -4D
Carbon
MW -4S
MW -5D
Total
MW -5S
Calcium
Iron
MW -6D
Strontium
Combined
MW -6S
MW-7BRA
X
Uranium
MW -7D
X
MW-7SR
X
Total
MW -8D
Chloride
Lead
MW -8I
Sulfate
Suspended
MW -8S
MW -9
X
Solids
MW-9BRA
X
Magnesium
MW-9DA
X
Vanadium
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Riverbend Steam Station Page 3 of 3 October 1, 2017

Revised Roxboro Steam Electric Plant Interim Monitoring Plan — Groundwater Only
Wells to be
Sampled
Sample for
Radionuclides
X
Regional Office Notes
ABMW-1
X
water level only
ABMW-IBR
X
ABMW-2
X
water level only
ABMW-2BR
X
ABMW-3
ABMW-3BR
ABMW-3BRL
ABMW-4
X
ABMW-4BR
X
ABMW-5
X
ABMW-5D
X
ABMW-6
ABMW-6BR
A13MW-7
water level only
ABMW-7BR
ABMW-7BRL
BG -1
X
BG-lBR
X
BG-1BRL
water level only
BG-1BRLR
X
New installation
BG -2
X
New installation
CW -1
CW -2
X
CW -2D
X
CW -3
CW -3D
CW -4
CW -5
X
GMW-10
GMW-11
GMW-6
X
GMW-7
GMW-8
GMW-9
MW -IBR
MW-2BR
MW-3BR
X
Roxboro Steam Electric Plant Page 1 of 3 October 1, 2017

MW-4BR
MW-4BRL
water level only
MW-5BR
X
MW-5D
X
MW-6BR
X
MW-6D
X
MW-7BR
MW-8BR
MW-9BR
X
MW-l0BR
X
MW-1lBR
X
MW-11D
X
New installation
MW-12BR
MW-13BR
X
MW-14BR
X
MW-15,BR
X
MW-15D
X
MW-16BR
X
MW-17BR
X
MW-18BR
X
MW-18D
X
MW-19BRL
X
MW-2
X
MW-20BRL
MW-21BRL
water level only
MW-22BR
MW-22D
MW-23BR
water level only
MW-23BRR
New installation
MW-24BR
MW-25BR
MW-26BR
MW-27BR
New installation
MW-28BR
New installation
MW-29BR
New installation
MW-30BR
New installation
MW-31BR
New installation
MW-32BR
New installation
MW-33BR
New installation
GPMW-1 S
New installation
GPMW-lD
New installation
Roxboro Steam Electric Plant Page 2 of 3 October 1, 2017

GPMW-lBR
Boron
New installation
GPMW-2D
Selenium
New installation
GPMW-2BR
Cadmium
New installation
GPMW-3D
Sodium
New installation
GPMW-3BR
New installation
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
Roxboro Steam Electric Plant Page 3 of 3 October 1, 2017

Revised L.V. Sutton Energy Complex Interim Monitoring Plan— Groundwater Only
Wells to be Sampled
Sample for
Radionuclides
M
Regional Office Notes
AW -1C
AW -2C
AW -2D
AW -3C
X
AW -4C
X
AW -5C
AW -5D
AW -6R -D
Installed in 1st Qtr. 2017 to replace AW -6
AW -6R -E
Installed in 1st Qtr. 2017 to replace AW -6E
AW -7R -D
Installed in 1 st Qtr. 2017 to replace AW -7D
AW -08C
AW -09C
AW -09D
MW -05C
X
MW-05CD
X
MW -05D
X
MW -05R -E
Replaced MW -5E
MW -7C
MW -8
X
MW -11
MW -12R
Installed in 1st Qtr. 2017 to replace MW -12
MW -16D
MW -19
MW -20
MW -20D
MW -21C
MW -22B
MW -22
MW -23B
MW -23C
MW -23D
X
MW -23E
X
MW -24R -B
MW -24R -C
MW -27B
MW -27C
X
MW -28B
MW -28C
MW -31R -C
X
Installed in 1st Qtr. 2017 to replace MW -31C
L.V. Sutton Energy Complex Page 1 of 2 October 1, 2017

MW -32C
X
MW -33C
X
MW -36C
X
MW -37B
X
MW -37C
X
MW-37CD
X
MW -37D
X
MW -37E
X
MW -38B
Carbon
MW -38C
X
MW -38D
X
MW -39B
Total
MW -39C
X
MW -39D
X
MW -40B
Combined
MW -40C
MW -40D
MW -41E
Uranium
SMW-01C
SMW-02C
SMW-03C
Total
SMW-04C
Chloride
SMW-5C
Potassium
SMW-06C
Suspended
SMW-06D
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
L.V. Sutton Energy Complex Page 2 of 2 October 1, 2017

Revised W. H. Weathersnoon Power Plant Interim Monitorine Plan — Groundwater Onlv
Wells to be
Sampled
Sample for Radionuclides
M
Regional Office Notes
AW -01D
AW -01I
AW -01S
AW -02D
AW -02S
AW -03D
AW -03I
AW -03S
BW -01
BW -02D
BW -02I
BW -02S
X
BW -03D
X
BW -03I
X
BW -03S
X
CCR -101 -BG
CAMA
X
CW -01
CW -02
CW -03
X
MW -01
X
MW -02
X
MW -03
X
MW -04
X
MW -05
X
MW -06
X
MW -07
X
MW -33D
MW -33I
MW -33S
MW -41D
MW -41I
MW -52
X
MW -53D
MW -53I
MW -54D
MW -55D
X
MW -55I
X
W. H. Weatherspoon Power Plant Page 1 of 2 October 1, 2017

PW -1 (DEP 2)
Minimum Parameters to be Analyzed
Aluminum
Boron
Copper
Mercury
Selenium
Thallium
Alkalinity
Cadmium
Hexavalent
Molybdenum
Sodium
Total Organic
Chromium
Carbon
Total
Antimony
Calcium
Iron
Nickel
Strontium
Combined
Uranium
Total
Arsenic
Chloride
Lead
Potassium
Sulfate
Suspended
Solids
Barium
Chromium
Magnesium
Radium 226
Sulfide
Vanadium
Total
Beryllium
Cobalt
Manganese
Radium 228
Dissolved
Zinc
Solids
W. H. Weatherspoon Power Plant Page 2 of 2 October 1, 2017

2017 Comprehensive Site Assessment Update October 2017
Belews Creek Steam Station
NCDEQ BACKGROUND DATASET REVIEW
(July 7, 2017)
SynTerra

Water Resources
Environmental Quality
July 7, 2017
Paul Draovitch
Senior Vice President
Environmental, Health & Safety
Duke Energy
526 South Church Street
Mail Code EC3XP
Charlotte, North Carolina 28202
ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. JAY ZIMMERMAN
Director
Subject: Duke Energy Submittal - Background Soil and Groundwater Statistical Methodology for
14 Duke Energy Facilities e-mails submitted May 26, 2017
Dear Mr. Draovitch:
The North Carolina Department of Environmental Quality (DEQ) has received and reviewed the May 26,
2017 e-mails from Duke Energy providing background soil and groundwater datasets. These site-specific
data were compiled following direction provided in an April 28, 2017 letter from DEQ to address technical
concerns related to site assessment and corrective action along with revisions to the Statistical Methods for
Developing Reference Background Concentrations for Groundwater and Soil at Coal Ash Facilities (HDR
Engineering, Inc. and Synterra Corporation, January 2017) technical memorandum (TM).
Attached are reviews of the soil and groundwater datasets for each Duke Energy coal ash facility. These
reviews identify data that are appropriate for inclusion in the statistical analysis to determine background
threshold values for both media following the methodology outlined in the TM. Additional requirements
related to soil and groundwater background determinations are specified for each facility. With approval
of these background datasets, preliminary background determinations for each media are expected to be
completed and provided within 30 days of receipt of this letter for those facilities that will submit
Comprehensive Site Assessments (CSAs) by October 31, 2017. For all other facilities that will submit
CSAs later, preliminary background determinations for each media are due within 60 days of receipt of this
letter.
If you have any questions, please feel free to contact Steve Lanter at [phone].
Sincerely,
S. Jayinlerman, P.G., Director
Division of Water Resources
Attachments: DEQ Background Dataset Reviews for the 14 coal ash facilities
cc: WQROS Regional Offices
WQROS Central File Copy
State of North Carolina I Environmental Quality I Division of Water Resources
Water Quality Regional Operations Section
1636 Mail Service Center I Raleigh, North Carolina 27699-1636
919-707-9129

Allen Steam Station
Groundwater
• The following background wells are appropriate for use:
o BG -1S, BG-2S/D, BG-4S/DBR, GWA-19S, GWA-21SBR, GWA-23S, and
GWA-26S/D
• The following background wells are NOT appropriate for use:
o BG -1D — Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included.
o BG-2BR — Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included. (Note: while there does
appear to be a topographic divide additional evaluation is needed to determine if
this is just a shallow divide or if it is indeed a divide for all flow layers.)
o AB-4S/DBR — Groundwater elevations below the nearest pond elevation has been
observed in several sampling events since installation of AB-4S/D. Due to the
potential for groundwater flow from the basin toward/through the well cluster this
location should NOT be considered a background location. AB-4BR should also
NOT be considered a background location (potential vertical migration from the
unconsolidated zone). (Note: Duke will evaluate further regarding pond elevation
utilized for assessment.)
o GWA-21D —Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included.
• All identified sample event dates are appropriate for use.
• The dataset for the shallow flow layer meets the minimum requirement of 10 samples after
excluding samples.
• The dataset for the deep flow layer does NOT meet the minimum requirement of 10
samples after excluding samples. Additional samples are require .
• The dataset for the bedrock flow layer does NOT meet the minimum requirement of 10
samples after excluding samples. Only 4 valid samples, but when additional evaluation
regarding nearest pond elevation used for the AB-4S/DBR locations is provided additional
samples may be available for inclusion.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
• The following background samples are appropriate for use:
o BG -1D (1.0-2.0), BG -1D (9.0-10.5), BG -1D (19.0-20.5), BG -1D (45-50), BG -2D
(1.0-2.5), BG -2D (8.5-10.0), BG -2D (18.0-20.0), BG -3D (1-2.5), BG -3D (13.5-
15), BG -3D (18.5-20), GWA-14D (10.0-12.0), GWA-8D (38.5-40), and GWA-8D
(48.5-50)
• The following background samples are NOT appropriate for use:
o GWA-15D —Sample is at or immediately adjacent to the waste boundary west of
the ash storage area and was also collected in fill material (according to boring log).
Allen Steam Station Pagel of 2

o GWA-5D —Sample is at or immediately adjacent to the waste boundary east of the
ash basin (immediately downgradient) and was also collected in fill material
(according to the boring log).
• The dataset meets minimum requirement of 10 samples after excluding samples.
• The reporting limits for Antimony and Thallium were above the IHSB PSRG Protection of
Groundwater values. Therefore, the number of useable values in the background dataset
is severely limited for these constituents. Additional samples analyzed at a lower detection
limit for these parameters are necessary.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Allen Steam Station Page 2 of 2

Asheville Steam Electric Plant
Groundwater
• All identified background wells are appropriate for use.
o MW -101 CB -01, CB -09, CB-09SL, MW -24S, CB -011), AMM -03B, and CB-09BR
o Duke Energy recommended adding wells GW -1, GW -1D, and GW-1BR to the
background dataset. Based on a review of the information provided, these wells
may be added to the background dataset. If these wells are added, the new raw
background dataset should be re -submitted to DWR.
• The datasets for each flow layer meets the minimum requirement of at least 10 samples.
• All identified sample event dates are appropriate for use.
• All identified outliers are acceptable and should be removed from the background dataset.
o If GW -1, GW -1D, and GW -IBR are added to the background dataset then re -test
the new dataset for outliers and re -submit to the DWR, including strikethroughs of
outliers and other unusable data (e.g high pH, high turbidity, autocorrelated data.
Soil
• The following background samples are appropriate for use:
o CB -01 SB (7-8), CB -01 SB (30-31), CB -09 SB (1-2), CB -09 SB (25-27), GW -01
SB (1-2), MW-11SB (1.5-2), MW -12 SB (1.5-2), MW-13SB (1.5-2), MW-13SB
(14.5-15), MW-14SB (1.5-2), MW -22 (1-2), MW-23BR (2-3), and MW-24SB (1-
2)
• The following background samples are NOT appropriate for use:
o MW -08 and MW -09 — Samples are at or immediately adjacent to the waste
boundary and should not be used as background locations, even though the samples
were collected above the seasonal high water table.
o CB -08, MW -03, MW -05, and MW -07 — Downgradient of site contamination.
o MW-13SB (22-22.5) — Sample was collected 3 -feet below the water table and
should not be used.
• The dataset meets the minimum requirement of at least 10 samples after excluding samples.
• The reporting limits for Antimony, Thallium, and Selenium were above the IHSB PSRG
Protection of Groundwater values. Therefore, the number of useable values in the
background dataset is severely limited for these constituents. Additional samples analyzed
at a lower detection limit for these parameters are necessary.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Asheville Steam Electric Plant Page 1 of 1

Belews Creek Steam Station
Groundwater
• All identified background wells are appropriate for use:
o BG -2S, BG -3S, MW -2025, MW -3, BG -1D, BG -2D, BG -3D, BG -202D, BG-2BR-
A, and MW-202BR
• The datasets for the shallow and deep flow layers meet the minimum requirement of 10
samples.
• The dataset for the bedrock flow layer does NOT meet the minimum requirement of 10
samples. Additional samples are required.
• All identified sample event dates are appropriate for use.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
• All identified background samples are appropriate for use:
o BG -1D (1-2), BG -1D (11), BG -1D (21), BG-lD (31), BG -2D (1-2), BG -2D (10-
12), BG -2D (20-22), BG -2D (30-32), BG -3S (1-2), BG -3S (10-12), BG -3S (20-
22), GWA-3D (34-35.5), GWA 4S (45-47), GWA-12D (10-12), GWA-12D (15-
17), GWA-12D (20-22), and GWA-12D (25-27)
• The dataset meets the minimum requirement of 10 samples.
• The reporting limits for Antimony, Thallium, and Selenium were above the IHSB PSRG
Protection of Groundwater values. Therefore, the number of useable values in the
background dataset is severely limited for these constituents. Additional samples analyzed
at a lower detection limit for these parameters are necessary.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Belews Creek Steam Station Page 1 of 1

Buck Combined Cycle Station
Groundwater
• The following background wells are appropriate for use.
o BG -18, BG-2S/D, BG-3SBRU, MW-6S/D, GWA-1S, MW -613R, and MW-8S/D
• The following background wells are NOT appropriate for use:
o BG-1D/BR— Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included.
o BG-2BR — Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included.
o MW-8BR — Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included.
• All identified sample event dates are appropriate for use.
• The datasets for each flow layer meets the minimum requirement of 10 samples after excluding
samples.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
The following background samples are appropriate for use:
o BG -1D (1-2), BG -1D (9.8-11.2), BG -1D (16.4-17.9), BG -2D (2), BG -2D (10-11.5),
BG -2D (13.5-15), BG-3BRU (1-2), BG-3BRU (10-10.5), BG-3BRU (20-20.5), GWA-
lOD (3.0), and GWA-11D (19-20.5)
The following background samples are NOT appropriate for use:
o GWA-11) — Sample was collected from 0.3-0.6 ft. bgs. Per IHSB Guidance, these
samples were taken too shallow.
o GWA-6BRU — Sample is located downgradient of the Cells 2 and 3 and within 1 foot
of the water table.
o GWA-7D — Sample is located downgradient of the Cells 2 and 3 and within 1 foot of
the water table.
o GWA-91) — Sample is located downgradient of Cell 1, both sample intervals were
collected in fill material (according to boring log) and one sample interval was
collected within 1 foot of the water table.
o GWA-12S —Sample is located downgradient of the ash basin.
o GWA-22D — Sample is located downgradient of Cell 1 and sample interval was
collected in fill material (according to boring log).
• The dataset meets minimum requirement of 10 samples after excluding samples.
• The reporting limits for Antimony, Thallium, and Selenium were above the IHSB PSRG
Protection of Groundwater values. Therefore, the number of useable values in the background
dataset is severely limited for these constituents. Additional samples analyzed at a lower
detection limit for these parameters are necessary.
• Please state whether any background sample included fill material. Samples containing fill
should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Buck Combined Cycle Station Page 1 of 1

Cane Fear Steam Electric Plant
Groundwater
• All identified background wells are appropriate for use:
o MW-15SU, MW-15SL, MW -16S, MW -09, MW-9BR, MW-15BR, and MW-16BR
• The datasets for all flow layers meet the minimum requirement of 10 samples.
• The following sample event dates are NOT appropriate for use:
o MW-15BR
■ 3/2/16 — Less than 60 days from previous sample.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
• The following background samples are appropriate for use:
o BG-01(Geosyntec)(2.0-2.5), BG-02(Geosyntec)(2.0-2.5), BG-03(Geosyntec)(2.0-
2.5), MW -09 SB(2-3), MW -09 SB (6-7), and MW -22 SB (3-4)
• The following background samples are NOT appropriate for use:
o MW-05BR SB(0-2), MW -09 SB(0-2), MW-l0BR SB(0-2), MW-12BR SB(0-2),
MW -15 SB(0-2), MW -20 SB(0-2), MW -22 SB(0-2), and MW -23 SB(0-2) — Per
IHSB Guidance, these samples were taken too shallow.
o BG-04(Geosyntec)(2.0-2.5) and BG-05(Geosyntec)(2.0-2.5) — Samples taken
down -gradient of 1985 Ash Pond.
• The dataset does NOT meet the minimum requirement of 10 samples. Additional samples
are required.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Cape Fear Steam Electric Plant Page 1 of I

James E. Rogers Energy Complex
Groundwater
• All identified background wells are appropriate for use.
o BG -1S, CCPMW-1S, MW -305, MW -325, GWA-245, GWA-255, GWA-30S, BG -
1D, MW -24D, MW -32D, GWA-24D, MW-32BR, CCPMW-1D, MW-24DR,
GWA-24BR, GWA-30BR, MW-22BR, and MW-22DR
• The datasets for all flow layers meet the minimum requirement of 10 samples.
• All identified sample event dates are appropriate for use.
• The following outliers are NOT appropriate for use and should be removed from the
background dataset:
Soil
o Total Dissolved Solids — 10,700,000 ug/L (saprolite)
o Total Dissolved Solids — 4,410,000 ug/L (saprolite)
o Total Dissolved Solids —407,000 ug/L (transition zone)
o Total Dissolved Solids —116,000 ug/L (transition zone)
o Iron — 31200 ug/L (transition zone)
o Vanadium — 3 ug/L (transition zone)
The following background samples are appropriate for use:
o BG -1D (3.5-5), BG -1D (8.5-10), BG -2D (3.5-5), BG -2D (8.5-10), BG -2D (18.5-
20), BG -2D (28.5-30), MW -30D (3.5-5.5), MW -30D (8.5-10), MW -30D (18.5-20),
MW -30D (28.5-30), MW -32D (3.5-5), MW -32D (8.5-10), MW -32D (18.5-20),
MW -32S (22.5-24), MW -42D (28.5-30), and GWA-25D (8.5-10)
The following background samples are NOT appropriate for use:
o BG -1S (3.5-5), BG -1S (8.5-10), MW -30S (4-5), MW -30S (9-10), MW -30S (19-
20), and MW -30S (28-29), — Only analyzed for TOC.
o GWA-1 OD — Located at or immediately adjacent to the waste boundary at Units 1-
4 basin.
o GWA-31D (7), GWA-31D (8.7), and GWA-31BR — Located at or immediately
adjacent to and downgradient of the waste boundary at Unit 5 basin and are adjacent
to a road and parking lot.
o MW -38D (33.5-35) — This location is downgradient of the Unit 5 Inactive Ash
Basin and adjacent to the Broad River.
o GWA-3D (48.5-50) — Location is downgradient of the Unit 5 Inactive Ash Basin.
o GWA-12BRU (20-23.5) — Location is immediately downgradient of Units 1-4
Inactive Ash Basin. May be close to water table and is near the Broad River.
o GWA-21BRU (5) — This sample may be immediately above the water table and
more importantly, the location is potentially downgradient of a basin and is situated
adjacent to the Broad River where there a potentially significant fluctuations of
water levels by a discharge point.
o GWA-22S (3-5) — Location is side gradient of the Active Ash Basin and adjacent
to the Broad River. The sample was collected within the screen interval of the well.
James E. Rogers Energy Complex Page 1 of 2

o GWA-27D (13.5-15) and GWA-27D (24.9) — Location is adjacent to and
downgradient of the impoundment. The sample was collected within the screened
interval of the well.
o MW-40BRU (3.5-5) — Location is adjacent to and downgradient of the Unit 5
Inactive Ash Basin and near the Broad River, and the sample was collected from
within the screened interval.
o GWA-61) (28.5-30) — Location is immediately downgradient of Unit 5 Inactive Ash
Basin and may be close to water table and is near the Broad River.
• The dataset meets the minimum requirement of 10 samples after excluding samples.
• The reporting limits for Antimony, Thallium, and Selenium were above the IHSB PSRG
Protection of Groundwater values. Therefore, the number of useable values in the
background dataset is severely limited for these constituents. Additional samples for these
three parameters are necessary.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• The following outlier is NOT appropriate for use and should be removed from the
background dataset:
o MW -32S (22.5-24)
■ Arsenic — 7.9 mg/kg
James E. Rogers Energy Complex Page 2 of 2

Dan River Combined Cycle Station
Groundwater
• The following background wells are appropriate for use:
o GWA-9S, BG -11), GWA-9D, MW -231), MW-23BR, BG -5S, BG -513, BG -10S,
BG -101), and BG-10BR
o GWA-9S/D and BG- IOS/D/BR appear to be appropriate for use; however, further
evaluation will be needed to determine whether these wells are truly located up -
gradient of the ash storages.
• The following background wells are NOT appropriate for use:
o GWA-12S/D —It appears that coal ash constituent boron, have been detected in soil
samples taken from this well.
o MW-20S/D — This well could be impacted by groundwater flowing from the
storage 1 area.
• The datasets for the shallow and deep flow layers meet the minimum requirement of 10
samples after excluding samples.
• The dataset for the bedrock flow layer does NOT meet the minimum requirement of 10
samples. Additional samples are required.
• All identified sample event dates are appropriate for use.
o Provisional background threshold value for hexavalent chromium (shallow flow
layer), vanadium (shallow flow layer), and radionuclides (shallow flow layer) are
based on a limited dataset. Additional samples are required.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
The following background samples are appropriate for use:
o BG -513(1-2), GWA-2D(19-20), GWA-9D(20-21.5), GWA-101)(9-10), SB -1(1-2),
SB -1(10-11.5), SB -1(15-16.5), SB -1(20-21.5), SB -1(25-26.5), SB -2(1-2), SB -
2(10 -11.5), SB -2(20-21.5), SB -2(30-31.25), SB -2(35-36), SB -2(65-65.3), SB -3(1-
2), SB -3(10-11), SB -3(20-21.5), and SB -3(35-36.5)
The following background samples are NOT appropriate for use:
o BG- 1D(0-2) — Per IHSB Guidance, this sample was taken too shallow.
o GWA-3D(5-6.5) — Sample taken in close proximity to Ash Storage 1.
o GWA-6S(9-11) — Sample taken down -gradient of Ash Basin Primary Cell
o GWA-10D(19-20) and GWA-10D(25) — Samples taken down -gradient of Ash
Storage 2.
o GWA-1113(10-11.5) — Sample taken down -gradient of Ash Storage 1.
Th dataset meets minimum requirement of 10 samples after excluding samples.
The reporting limits for Antimony, Thallium, and Selenium were above the IHSB PSRG
Protection of Groundwater values. Therefore, the number of useable values in the
background dataset is severely limited for these constituents. Additional samples analyzed
at a lower detection limit for these parameters are necessary.
Dan River Combined Cycle Station Page 1 of 2

• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Dan River Combined Cycle Station Page 2 of 2

H. F. Lee Enerev Complex
Groundwater
• The following background wells are appropriate for use:
o AMW-11S, AMW-12S, AMM -13S, AMW-17S, IMW-01S, IMW-03S, AMW-
11BC, AMW-12BC, AMW-13BC, AMW-16BC, IMW-01BC, IMW-02BC, and
IMW-03BC.
o AMW-016BC —The location maybe near the contact with the Black Creek. Please
confirm.
The datasets for the surficial and Cape Fear flow layers meets the minimum requirement
of 10 samples.
The dataset for the Black Creek flow layer does NOT meet the requirement of 10 samples.
Additional samples are required.
The following sample event dates are NOT appropriate for use.
o AMM -12S
■ 3/1/16 — Less than 60 days from previous sample.
o AMW-13S
■ 3/1/16
—Less than 60 days from previous sample.
o AMW-12BC
■ 3/1/16
— Less than 60 days from previous sample.
o AMW-13BC
■ 3/1/16
— Less than 60 days from previous sample.
o IMW-0lBC
■ 3/4/16
— Less than 60 days from previous sample.
o IMW-02BC
• 3/3/16 — Less than 60 days from previous sample.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
The following background samples are NOT appropriate for use:
o AMW-12 SB (5-6) — Sample may have been taken within 1 foot of the seasonal
high water table.
o IMW-05 SB (0-2.5) and IMW-05 SB (4-6). This location is in very close proximity
to the southeast corner of Inactive Basin 3 and possibly influenced by the presence
of the ash basin. Per IHSB Guidance, these samples were taken too shallow.
o AMW-18 SB (0-2.5) and AMW-18 SB (3-5). Samples were collected from the
core of the plume migrating from the Active Basin.
o AMW-04 SB (1-2) and AMW-04 SB (4-5). Samples are located at the western end
of the Active Basin, adjacent to the Neuse River.
o AMW-16BC (19-21).
o AMW-11 (0-2), AMW-12 SB (0-2), AMW-13 SB (0-2), and AMW-16BC (0-2) -
Per IHSB Guidance, these samples were taken too shallow.
H. F. Lee Energy Complex Pagel of 2

• The dataset does NOT meet the requirement of 10 samples. Additional samples are
required.
• The reporting limits for Antimony and Thallium were above the IHSB PSRG Protection of
Groundwater values. Therefore, the number of useable values in the background dataset
is severely limited for these constituents. Additional samples analyzed at a lower detection
limit for these parameters are necessary.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
H. F. Lee Energy Complex Page 2 of 2

Marshall Steam Station
Groundwater
• The following background wells are appropriate for use.
o GWA-4S/D, GWA-5S/D, GWA-6S/D, GWA-8S/D, GWA-12SBR, BG-3BR, MS -
10, MW -4, and MW -4D
• The following background wells are NOT appropriate for use:
o BG-lBR — Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included.
o GWA-12D — Recently reinstalled due to water quality issues and reevaluation as
background location is necessary before being included.
• The datasets for each flow layer meets the minimum requirement of 10 samples after
excluding samples.
• All identified sample event dates are appropriate for use.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
• The following background samples are appropriate for use:
o BG -3D(1-2), BG -313(10-12), GWA-2DA(3-5), GWA-2DA(8-10), GWA-4D(52-
53), GWA-5D(27.5-29.0), GWA-14S(3-5), and GWA-14S(8-10)
• The following background samples are NOT appropriate for use:
o GWA-IBR — Sample is within the waste boundary downgradient of the ash basin
and coal pile.
o MW-14BR — Sample is located downgradient of the ash basin and Phase I Landfill
(unlined).
• The dataset does NOT meet minimum requirement of 10 samples. Additional background
samples are required.
• The reporting limits for Antimony and Thallium were above the IHSB PSRG Protection of
Groundwater values. Additional samples analyzed at a lower detection limit for these
parameters are necessary.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Marshall Steam Station Page 1 of 1

Mayo Steam Electric Plant
Groundwater
• The following background wells are appropriate for use:
o MW -125, BG -02, MW -12D, BG -01, MW-13BR, and MW-14BR
• The following background wells are NOT appropriate for use:
o MW-IOBR
• The dataset for the surficial flow layer does NOT meet the minimum requirement of 10
samples. Additional samples are needed.
• The datasets for the transition zone and bedrock flow layers meets the minimum
requirement of 10 samples.
o Provisional background threshold values for radionuclides in the transition zone
flow layer are based on a limited dataset. Additional samples are required.
• The following sample event dates are NOT appropriate for use:
o BG -01
Soil
■ 11/3/2015 —Less than 60 days from previous sample.
■ 1/8/2016 — Less than 60 days from previous sample.
• 9/8/2016 — Less than 60 days from previous sample.
■ 3/28/17 — Less than 60 days from previous sample.
o MW-10BR
■ 1/7/16 —Less than 60 days from previous sample.
■ 9/7/16 —Less than 60 days from previous sample.
o MW-13BR
■ 1/7/2016 — Less than 60 days from previous sample.
• 9/6/2016 — Less than 60 days from previous sample.
All identified outliers are acceptable and should be removed from the background dataset.
The following background samples are appropriate for use:
o MW-08BR (0.75-1.25), MW-08BR (25.5-26), MW-IOBR (0.75-1.0), MW -12D (1-
2), MW -12D (25-26), SB -01 (1-2), and SB -01 (13.5-14.5)
The following background samples are NOT appropriate for use:
o MW-03BR (0.8-1.25) and MW-15BR (0.5-1) — Samples taken down -gradient of
Ash Basin.
o MW-11BR (0-2) and MW-13BR (0-2) —Per IHSB Guidance, these samples were
taken too shallow.
o SB -02 (0.5-2) and SB -02 (11.0-12.5) — Boring log indicates the presence of coal
ash.
o SB -03 (5-6) and SB -03 (17-18.5) — Boring log indicates the presence of coal ash.
o SB -05 and SB -06. Sample locations were adjacent to the 1981 landfill.
The dataset does NOT meet the minimum requirement of 10 samples. Additional samples
required.
Mayo Steam Electric Plant Page 1 of 2

• The reporting limits for Antimony and Thallium were above the IHSB PSRG Protection of
Groundwater values. Therefore, the number of useable values in the background dataset
is severely limited for these constituents. Additional samples analyzed at a lower detection
limit for these parameters are necessary.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Mayo Steam Electric Plant Page 2 of 2

Riverbend Steam Station
Groundwater
• The following background wells are appropriate for use:
o BG -1S, MW-7SR, MW -7D, BG -4S, GWA-14S, BG -41), BG -5D, and BG-5BR
o MW -71) was listed under the shallow flow laver. Please re-evaluate.
• The following background wells are NOT appropriate for use:
o GWA-5S — Groundwater water elevations were similar and sometime lower than the
historical water elevation of ash basin. Also, the wells are within compliance boundary
and not far from the waste boundary.
• The datasets for shallow meets the minimum requirement of 10 samples after excluding
samples.
• The datasets for the deep and bedrock flow layers does NOT meet the minimum requirement
of 10 samples. Additional samples are required.
• All identified sample event dates are appropriate for use.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
• The following background samples are appropriate for use:
o BG -1D (5-6), BG -1D (14-15), BG -1D (24-25), BG -2D (3.5-5), BG -2D (48-49), BG -
3D (3-5), BG -31) (18.5-20), BG -3D (23-24), GWA-51) (58.5-60), GWA-6D-1(43.5-
45), GWA-6D-2(48.5-50), GWA-21D(3.5-5), GWA-211)(8.5-10), GWA-21D(18.5-
20), GWA-21D(48.5-50), MW-7BR(43.5-45), and OB -2(38.5-40.0)
• The following background samples are NOT appropriate for use:
o GWA-3D(18.5-19) — Sample taken down -gradient of Ash and Cinder Storage Areas.
o GWA-7S(7.0-8.0) — Sample taken down -gradient of Ash Basins.
o GWA-8D(8.5-10) — Sample taken down -gradient of Ash Basins.
o GWA-9D (1), GWA-10S (8-9), and MW -15D (3.5-5) — Downgradient location and
maybe within the High Seasonal Water Table.
o GWA-20D(40-41.5) — Sample taken in close proximity to Ash Storage Area.
o GWA-22D(38.5-40.0) — Sample taken in close proximity to Ash Storage Area.
o GWA-23D(33.5-35) — Sample taken within the waste boundary of the Ash Storage
Area.
o OB -1(33.5-35.0) — Sample taken inclose proximity to Ash Basin.
• The dataset meets the minimum requirement of 10 samples after excluding samples.
• The reporting limits for Antimony, Thallium, and Selenium were above the IHSB PSRG
Protection of Groundwater values. Therefore, the number of useable values in the background
dataset is severely limited for these constituents. Additional samples analyzed at a lower
detection limit for these parameters are necessary
• Please state whether any background sample included fill material. Samples containing fill
should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Riverbend Steam Station Page 1 of 1

Roxboro Steam Electric Plant
Groundwater
• The following background wells are appropriate for use:
o BG -1, MW -15D, MW -18D, BG-01BR MW-IOBR, MW-14BR, MW-15BR, MW-
18BR, and MW-19BRL
• The following background wells are NOT appropriate for use:
o MW-13BR, MW-16BR, and MW-17BR
• The datasets for all flow layers meet the minimum requirement of 10 samples after
excluding samples.
• The following sample event dates are NOT appropriate for use:
o BG -01
■ 9/8/2016 — Less than 60 days from previous sample.
■ 11/16/16 —Less than 60 days from previous sample.
o BG-01BR
■ 7/9/15 — Less than 60 days from previous sample.
o MW-17BR
• 11/10/16 —Less than 60 days from previous sample.
All identified outliers are acceptable and should be removed from the background dataset.
Soil
• The following background samples are appropriate for use:
o MW -08 (14-16), MW -08 (21-23), MW-13BR (22-24), MW-14BR (1-1.25), MW-
14BR (31-31.5), MW-14BR (37.5-38), MW -17 (29-31), MW -18 (31-33), and MW -
18 (37-38)
• The following background samples are NOT appropriate for use:
o MW -07 (0-2), MW -08 (0-2), MW-IOBR (0-2), MW-13BR (0-2), MW -15 (0-2),
MW -16 (0-2), and MW -18 (0-2) — Per IHSB Guidance, these samples were taken
too shallow.
• The dataset does NOT meet the minimum requirement of 10 samples. Additional samples
are required.
• The reporting limits for Antimony and Thallium were above the IHSB PSRG Protection of
Groundwater values. Samples for these two parameters need to be reported below these
values.
• Please state whether any background sample included fill material. Samples containing
fill should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
Roxboro Steam Electric Plant Page 1 of 1

�n

L. V. Sutton Energy Complex
Groundwater
• All identified background wells are appropriate for use:
o MW -05A, MW -0513, MW -3713, MW -0413, MW -05C, MW -08, MW -37C, MW-05CD,
MW -05D, MW -37D, MW -05E, and MW -37E
o Lower Surficial Aquifer — An adequate dataset has been provided for all constituents,
with the exception chromium (VI). Additional samples are planned for collection to
bring the total number of valid chromium (VI) samples to ten by second quarter 2017.
• The datasets for the upper and lower surficial flow layer meet the minimum requirement of 10
samples.
• The dataset for the Upper Peedee flow layer does NOT meet the minimum requirement of 10
samples. Additional samples are planned for collection to bring the total number of valid
samples to ten (second quarter 2017 at the earliest). It was agreed upon to use a pH of less than
or equal to 9.7 S.U. as the upper threshold for these zones in the Peedee aquifer.
• The dataset for the Lower Peedee flow layer does NOT meet the minimum requirement of 10
samples. New and replacement wells have been added to the groundwater monitoring network
(MW -5R -E, MW -8E, MW -41E). Additional samples are planned for collection to bring the
total number of valid samples to 10 (second quarter 2017 at the earliest). It was agreed upon
to use a pH of less than or equal to 9.7 S.U. as the upper threshold for these zones in the Peedee
aquifer.
• All identified sample event dates are appropriate for use.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
• The following background samples are appropriate for use:
o AW -02C (10-11) and MW -37C (4-6)
• The following background sample are NOT appropriate for use:
o AW -01C (0-2), AW -02C (0-2), AW -03C (0-2), AW -04C (0-2), AW -06D (0-2), AW -
07D (0-2), MW -37C (0-2), SMW-01C (0-2), SMW-02C (0-2), SMW-03C (0-2),
SMW-04C (0-2), SMW-05C (0-2), and SMW-06D (0-2) — Per IHSB Guidance, these
samples were taken too shallow.
o AW -05C (4-6) and AW -05C (9-11) —Samples are down -gradient of the ash pond.
• The dataset does NOT meet the minimum requirement of 10 samples. Additional samples are
require .
• The reporting limits for Antimony, Cobalt, and Thallium were above the IHSB PSRG
Protection of Groundwater values. Therefore, the number of useable values in the background
dataset is severely limited for these constituents. Additional samples analyzed at a lower
detection limit for these parameters are necessary.
• Please state whether any background sample included fill material. Samples containing fill
should be omitted from the raw background dataset.
• All identified outliers are acceptable and should be removed from the background dataset.
L. V. Sutton Energy Complex Page 1 of 1

W.H. Weatherspoon Power Plant
Groundwater
• All identified background wells are appropriate for use.
o BW -02S, BW -03S, CCR -101-13G, MW -01, BW -03I, and BW -03D
• The dataset for the surficial flow layer meets the minimum requirement of 10 samples
• The dataset for the Lower Yorktown does NOT meet the minimum requirement of 10
samples. Additional samples are required.
• The dataset for the PeeDee does NOT meet the minimum requirement of 10 samples.
Additional samples are required.
• The following sample event dates are NOT appropriate for use.
o BW -03S
■ 3n116 — Less than 60 days from previous sample.
• All identified outliers are acceptable and should be removed from the background dataset.
Soil
No soil background data was provided. Please coordinate the collection of background
soil data with the DWR Fayetteville Regional Office.
W. H. Weatherspoon Power Plant Page 1 of I

2017 Comprehensive Site Assessment Update October 2017
Belews Creek Steam Station
ZIMMERMAN TO DRAOVITCH
(September 1, 2017)
SynTerra

Water Resources
Environmental Quality
September 1, 2017
Paul Draovitch
Senior Vice President
Environmental, Health & Safety
Duke Energy
526 South Church Street
Mail Code EC3XP
Charlotte, North Carolina 28202
ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. JAY ZIMMERMAN
Director
Subject: Approval of Provisional Background Threshold Values for Belews Creek Steam
Station
Dear Mr. Draovitch:
The North Carolina Department of Environmental Quality's Division of Water Resources (DWR)
has reviewed Duke Energy's calculated provisional background threshold values (PBTVs) for soil
and groundwater for the subject facility. DWR calculated PBTVs based on the vetted background
data in the letter to Duke Energy dated July 7, 2017, using the Revised Statistical Methods for
Developing Reference Background Concentrations for Groundwater and Soil at Coal Ash
Facilities dated May 26, 2017. It should be noted that Duke Energy supplied additional data on
August 8, 2017, and September 1, 2017, on which their final calculations were based.
Per 15A NCAC 02L .0202(b)(3), where naturally occurring substances exceed the established
standard, the standard shall be the naturally occurring concentration as determined by the Director.
Therefore, PBTVs that are calculated to be above the 15A NCAC 02L .0202 groundwater
standards or Interim Maximum Allowable Concentrations (IMACs) and accepted by DWR shall
become the enforceable groundwater standard. Otherwise, the enforceable groundwater standards
shall be those listed under 15A NCAC 02L .0202(h) including any effective IMACs.
The attachments document DWR's concurrence/non-concurrence with Duke Energy's calculated
PBTVs for groundwater and soil. For all Duke Energy's calculated PBTVs that DWR finds
acceptable, DWR hereby approves those values. If DWR does not find the Duke Energy's
calculated PBTVs acceptable, justification is provided on the attachments. Duke Energy will be
responsible to provide revised values for DWR to review and approve.
Please note that the approved PBTVs are based on the current data available. DWR recognizes
that, as new data is gathered going forward, the approved PBTVs may be refined. Thus, there will
be need for a periodic review of the data and recalculation of the PBTVs. The timeframes for the
periodic review will established by DWR at a later date and any revised PBTVs will be subject to
approval by the DWR's Director.
State of North Carolina I Environmental Quality I Division of Water Resources
Water Quality Regional operations Seetiou
1636 Mail Service Center I Raleigh, North Carolina 27699-1636
919-707-9129

Along with the specific comments provided on the attachments, DWR offers the following general
comments with regards to the PBTVs
Outliers are identified with three statistical lines of evidence; Box Plots, Q -Q Plots, and
95% Significance Levels. Based on these lines of evidence, if Duke Energy chooses not
to exclude an outlier, then additional rationale or justifications shall be provided.
The PSRG for Chromium shall be the more conservative value for Chromium (VI) which
is 3.8 mg/kg.
If you have any questions, please contact Shuying Wang (Winston-Salem Regional Office) at
[phone] or Steve Lanter (Central Office) at [phone].
Sincerely,
S. Jay Zimmerman, P.G., Director
Division of Water Resources
Attachments
cc: WSRO WQROS Regional Office Supervisor
WQROS Central File Copy

2017 Comprehensive Site Assessment Update October 2017
Belews Creek Steam Station
SynTerra
NCDEQ BACKGROUND THRESHOLD VALUE
APPROVAL ATTACHMENTS
(September 1, 2017)

NA -Not Applicable
NO - Not Detected
NE - Not Established
mp/L - milligram per liter
pCBL - picocuries per liter
Radimn (Total) - Radium -226 and Radium -228 emobined
-Th. 15A NCAC 02L Standard's 10 mg/L for Nitrate and I mg/L for Nitrite (added for a total of l I mg/L)
S.U. - Standard Unit
TOC - Total Organic Carbon
TDS - Total Dissolved Solids
,,/mL -micrograms per milliliter
pg/L - micrograms per liter
Uranium (Total) - Uranium -233, Uramumd34, Uranium -236, and Uranium -238 combined
Belews Creek Steam Station - Groundwater Provisional Background
Threshold Values
Duke f ne_ra.( alauLaed
l'D i Vs
15A NCAC 02L
DWR Concurrence(Acceptable/Not Acceptable)
Reporting
_
Parameter
Units
_}low l nit
T
_
Standard or
Flow Unit
Comments
Shallow DV,P
8ednn6
IMAC
Shallow
Deep
Bedrock
H
S.U.
5.1-6.03
5.19-7.02
-+
-
6 3-6 5
-
6.5-8.5
Acceptable
Acceptable
Acceptable
Not evaluated because the values me below the groundwater standards or no standard is established.
Alkalinitymg/L 22 9 63' 3LJ NE Acceptable Acceptable Acceptable
Alumina
AgfL
860
_ _y
140
-_
Leo
NE
Acceptable
Acceptable
Acceptable
Antimony
I__
I1___ I
1
_
0.5
1
Acceptable
Acceptable
Acceptable
Arsenic
L
i
1
_
10
Acceptable
Acceptable
Acceptable
Barium,
1191L
_
58
_ _
12.6
_
-u-51
6..2
700
Acceptable
Acceptable
Acceptable
Beryllium,
L
0_862
0.219
0.2
4
Acceptable
Acceptable
Acceptable
Bicarbonate
mg/L
22_1
629
.6
NE
Acceptable
Acceptable
Acceptable
Boron
L
ND
_
IT_ %1)
_
_ 5_n __
700
Acceptable
Acceptable
Acc table
Not evaluated because the values are below the groundwater standards or no standard is established.
Cadmium
L
1 _
_ 1 -
i
0 08
2
Acceptable
Acceptable
Acceptable
Calcium m L 3.60 lit NE Acceptable Acceptable Acceptable
Carbonate
L
?D
tiD
_10.3_ _
5
NE
Acceptable
Acceptable -
Acceptable
Chloride
mg/L
IS
_
20.1
_ _
i
250
Acceptable
Acceptable
Acceptable
Chromium (VI) L 1.75 0.411_ t 033 NA Acceptable Acceptable Acceptable
Chromium
4.72
_
_ _• 3.?_
5-3
10
Acceptable
Acceptable
Acceptable
Cobalt URIL I 0,5110 1,6 0.76 1 Acceptable Acceptable Acceptable
copper
1191L
2.7
5
9.7
1000
Acceptable
Acceptable
Acceptable
Not evaluated because the values are below the g2undwater standards or no standard is established.
Iron
L
750
240
228
300
Acceptable I
Acceptable
Acceptable
Lead
L
1
I
0.11
15
Acceptable
Acceptable
Acceptable
Not evaluated because the values are below the groundwater standards or no standard is established.
Magnesium
mg/L
3.41
6.94
3.35
NE
Acceptable
Acceptable
Acceptable
Manganese
µ
27.9_
55
9.9
50
Acceptable
Not Acceptable
Acceptable
Dee should be 13 (or 2L) because of five ideatified omliers.
Mere
L
ND
ND
0.2
1
Acceptable
Acceptable
Acceptable
Methane
991L
2.65
(0
NE
Acceptable
Acceptable
Acceptable
Mol bdeaum
L
1
_ _ _2.64
-t- 1.3
3.7
NE
Acceptable
Acceptable
Acceptable
Nickel
µ
4.26
4.67
3.2
100
Acceptable
Acceptable
Acceptable
Nitrate + Nitrite
mg-N/L
3.6?
_
4.19_
0.17
11*
Acceptable
Acceptable
Acceptable
Potassium
m
5
5
5.15
NE
Acceptable
Acceptable
Acceptable
Selenium
%D
_
0.5
20
Acceptable
Acceptable
Acceptable
Not evaluated because the values are below the groundwater standards or no standard is established.
_ _ND
Sodium mg/L 5?2 1 (1.'- 12 NE Acceptable Acceptable Acceptable
Strontium
56.5
_ _ _
r 68 5
_ _
I ItU_
NE
Acceptable
Acceptable
Acceptable
Sulfate
mg/L
1 ,! i
26
250
Acceptable
Acceptable
Acceptable
_035
Sulfide mg/L _NT r ND _x_0.1 NE Acceptable Acceptable Acceptable
TDS mg/L 85 14_X 1 133 500 Acceptable Acceptable Acceptable
Thallimn
µg'L_U
_
_
2
_
1).1
0.2
Acceptable
Acceptable
Acceptable
TOC
mg/L
-N 1)
_-}
_NJ
+_
_
10.2
NE
Acceptable
Acceptable
Acceptable
Shallow should be 1.33 because 2.01 was identified as an outlier.
Vanadium L 1 45 11.82 0.3 Not Acce table Acceptable Acceptable
Zinc
L
_1.89__
10
_
I
16
1000
Acceptable
Acceptable
Acc table
Not evaluated because the values are below the groundwater standards or no standard is established.
_ _43.2_
Radium (Total) pCi/L 8. �q- 1.I 0.466 NEAcceptable Acceptable Acceptable
Uranium (Total) L OAnr� O.oU05 0.Ot815q NE Acc table Acceptable Acceptable
NA -Not Applicable
NO - Not Detected
NE - Not Established
mp/L - milligram per liter
pCBL - picocuries per liter
Radimn (Total) - Radium -226 and Radium -228 emobined
-Th. 15A NCAC 02L Standard's 10 mg/L for Nitrate and I mg/L for Nitrite (added for a total of l I mg/L)
S.U. - Standard Unit
TOC - Total Organic Carbon
TDS - Total Dissolved Solids
,,/mL -micrograms per milliliter
pg/L - micrograms per liter
Uranium (Total) - Uranium -233, Uramumd34, Uranium -236, and Uranium -238 combined

NA - Not applicable (dataset contains zero valid samples)
ND - Non -Detect
NE - Not Established
mg/kg - milligrams per kilogram
S.U. - Standard Unit
Belews Creek Steam Station - Soil Provisional Background Threshold Values
Parameter
Reporting
Units
Duke Icnerg}
Calculated
PIS I S.t
PSRG Protection
of Groundwater
DWR Concurrence
(Acceptable/Not
Acceptable)
Comments
H
S.U.
-13 5 8
NE
Acceptable
Aluminum
mg/kg
3125:
NE
Acceptable
Antimony
mg/kg
0.6
0.9
Acceptable
Arsenic
m
12.64
5.8
Acceptable
Barium
mgfkg
139
580
Acceptable
Beryllium
mg/kg
19.3
63
Acceptable
Boron
m k
_ _
1
45
Acceptable
Cadmium
m kg
_
0.032
3
Acceptable
Calcium
mg/kg
450
NE
Acceptable
Chloride
mg/kg
_
14
NE
Acceptable
Chromium
mg/kg
41.09
360000 (3.8)
Not Acceptable
Use the PSRG for Chromium (IV) of 3.8 mg/kg. PBTV for Chromium should be 36 mg/kg instead of 41.1 mg/kg because 43 was statistically
identified as outlier.
Cobalt
mg1kg
51.01
0.9
Acceptable
Copper
mg/kg
28.43
700
Acceptable
Iron
mg/kg
40,100
150
Acceptable
Lead
mg/kg
39.72
270
Acceptable
Magnesium
mg/kg
3600
NE
Acceptable
Manganese
mglkg
Ill'
65
Acceptable
Mercury
mg/kg
0.1
1
Acceptable
Molybdenum
mg/kg
9.8
NE
Acceptable
Nickel
m
11.6
130
Acceptable
Nitrate as N
mg/kg
0.3
NE
Acceptable
Potassium
mglkg
2114
NE
Acceptable
Selenium
mgfkg
5,431
2.1
Acceptable
Sodium
to g
393
NE
Acceptable
Strontium
mg/kg
9
NE
Acceptable
Sulfate
mg/kg
12
250
Acceptable
Thallium
mg/kg
0.852
0.28
Not Acceptable
PBTV for Thallium should be 0.69 mg/kg instead of 0.85. Please recalculate to verify your result
Vanadium
mg/kg
12t,
6
Not Acceptable
PBTV for Vanadium should be 114 m instead of 127 because, in addition to 280, 141 was also statistically identified as an outlier.
Zinc
mg/kg
51.'r.
1200
1 Acceptable
NA - Not applicable (dataset contains zero valid samples)
ND - Non -Detect
NE - Not Established
mg/kg - milligrams per kilogram
S.U. - Standard Unit